I'm new to this forum but I need a little help w my Peugeot 406. I hope I'm at a right place!

So my car is at the mechanic right now as I had a problem with a clutch (pedal to the floor, and it doesn't work at all). It turned out that the clutch cylinders (master and slave) need a replacement - so far it's fine.
My problem is that we cannot get the replacement parts... The mechanic has tried several aftermarket parts, but they didn't fit. Original part is not available anymore...
Could anyone help me, does anyone have a spare clutch cylinder? I'm attaching a few pics about them.
(The car details: V6 - ES9J4 engine, 1998, it's a 406 Break, but this doesn't really matter I guess.)
Thanks!