If you don't have the original clutch forks and TO bearing hub carrier and arm you'll need to obatin those too, not inexpensive. Dennis Quella is a good source he used to do a lot of hydraulic throwout conversions on Panteras, so has take out parts and is knowledgeable on your possible hydraulic TO issues.
There is a TO bearing hub carrier on Ebay right now....
If your hydraulic TO is constantly failing then you may have too much throw on it, half the battle is getting the things setup correctly. A clutch peddle stop is often required to prevent overthrowing.