Audi transaxle issue

So had it out today and the same thing happened. Not to such an extent. Clutch got air in it within 15 minutes so I'm guessing the seal has gone. What's the best thing to replace the slave cylinder with? I've read they originals from the 016 are hard to source. Should I just try to find one and make up a bracket to fit it? (it's held in by a cotter pin I believe)