I recently was given a mk2 by a mate -it did have a few issues to sort which I have now sorted
I also converted it to .20 and made a few brass and aluminium bits to replace plastic parts -just wish I had time to test it now
https://imgur.com/wFaaHkU
https://imgur.com/Ifpw2I3
https://imgur.com/W13tErt
https://imgur.com/8wlnsqG