I am upgrading the bulbs in an old fluorescent work light to LED bulbs. I have pulled the ballasts, and remove the starters from the Tombstones pictured below. Is it safe to use these tombstones without the starters in them, or is there a replacement I should look for?
Use a double-ended LED tube. (not single-ended; they're shady and hard to wire, particularly on this fixture). Use a voltmeter to find a terminal on the starter that is wired directly to one of the tombstone terminals. Use that one.
I wouldn't recommend trying to replace the tombstones. Those look pretty specialized.
That's a combination I haven't run across before.
Loosen one (perhaps two?) more screw(s) and remove the starter socket entirely. If the arrangement of the light is such that the thing won't stay in place without it, just bypass so your LED wiring is connecting directly to the tombstone, not to the starter socket. But if you can remove the socket and the tombstone will still be held properly in the fixture, ditch the socket, use the tombstone.
Might need to do a bit of continuity testing with a multimeter to sort out the right screws for your new wiring, especially if you are stuck with the socket for mechanical reasons.
Don't bother. Either upgrade whole fixture or use original tubes.
Linear LED fixtures are very cheap, rivaling price of retrofit tubes alone. Retrofits are mostly workmanship-saving measure, when it doesn't involve rewiring.
The problem with retrofits is that by definition LEDs in retrofits can never work as well as LEDs in fixtures designed for LEDs. LEDs in retrofits are not cooled as much as they need, they shine differently than original tubes, choice of retrofits from reputable makers is very small, etc.
Also, the difference of power efficiency of LEDs vs FLs is not as big as vs incandescent so potential savings rarely exceed costs.
/edit: on a second thought, despite this advice I can still answer your questions:
Is it safe to use these tombstones without the starters in them
Yes. You are already rewiring, so all you need is to identify the leg without starter socket and wire that leg.
The only safety issue would be someone poking things into empty starter socket. It's hardly possible in your scenario (as the tube blocks access to the starter), but you should mask the empty socket with insulation tap to mark it as unused.
or is there a replacement I should look for?
If you're asking about replacement tombstones then very unlikely. Fixtures are designed for one particular model of tombstone. Other models usually have different mounts and/or height. There's no need for replacement.
If you're asking about replacement starters, then it's in the manual of your retrofit tubes. Some models come with a dedicated starter dummy that you should use, some require to leave an empty socket and other don't care at all; you're supposed to leave old starter in place. Follow the manual.
Another thought: you can consider retrofit that is glued onto the reflector. It will have advantages of better heat dissipation and not needing tombstones at all.
Leaving the starter out will leave no connection between there screw terminal in pic #1 and the tombstone.
There are many wiring configurations for LED retrofit tubes, so a definitive answer about necessity to replace sockets is difficult without knowing what the needs for the particular product are.
The only clearly safe configuration with those sockets are SEP (single end power) lamps because you could power the opposite end and leave that end as just a lamp holder.
Beyond that if you need double ended feed you could connect separate wires to the two screws in pic #3, and disregard the terminal in pic #1. This would make connection to the lamp socket, but would also leave one terminal of the missing fluorescent starter socket uselessly connected to the circuit. The odds are pretty small that any finger, tool, or part of the fixture would make unplanned contact, but I don't like advising to go beyond UL/ETL approval specifying to use only per instructions.
I think separating the starter socket from the lamp socket has some issues too. The existing terminal screws on the bottom appear long enough to reach through the starter base into the tombstone. If you can remove those screws without damage you would likely need shorter replacement screws with heads big enough to hold wires. Once you remove the screws the tombstone contacts may not stay in place making screws hard to re-install. Be careful when removing the screws that the threads have not been modified to prevent removal. Replacement sockets may be the best route if proper mounting is possible.
Having replaced normal fluorescents with LEDs myself, I have a few comments in case they were not obvious.
If you are doing this to save power, then you need to remove the ballasts (which you have), otherwise the savings are not as much as you might expect. But the ballasts can be left in.
You need to remove the original starters, LEDs do not need them.
Most LED battens will come with a LED starter. This is simply a short. If you are rewiring the fixture, you can just bypass the starter socket.
To get the most out of them, you really need an electrician to do the rewiring, especially if this is a work environment.
