I just got one from the EE last month - not cheap but I needed it. Patience and you will find what you need on the secondary market but you will just need to keep at it. I dont know if Valmet.org is still functioning but I bet not. EE, Sturmgewehr and GB are good bets. When I grabbed the one on EE, I was looking for something else but there it was.
I am still kicking myself - there was a little gun shop in NYS a town or 2 next to where the importer was located when they stopped importing in the late 80s. No mags when I found them, but they had a ton of smaller parts, firing pins, screws and those buffers - I got 2 - the owner said he bought everything the importer had when they closed up shop. I knew I should have bought more but no $$$ at the time.