Is there a difference between a gas and a diesel clutch slave cylinder? I can find a gas one but nothing on web for diesel.
Depends on what kind of vehicle you’re talking about. There’s nothing inherently different about a diesel engine that would call for a different slave cylinder. It’s probably just a difference in where it mounts and where the connections are, though the diesel slave clutch might be heavier duty if you’re talking about a truck-based camper and not a Vanagon. If you can post what kind of camper you’re talking about, we might be able to be more helpful.
Get a new one, compare it to the old one, and if they appear to be the same, go with it!
Tester
It’s a 1981 Toyota Diesel Sunrader—Vin# JT4LN44D9B0049686