Butt plate for Soviet Laminate stock...

[Boris Badinov]

Are they interchangeable with butt plates on the soviet hard wood stocks?

[running-man]

Nope, they are two distinct buttplates.  You can make one fit and vice versa, but they have distinctly different inletting of the buttstock so you could get a gap that might look a bit ratty in some instances when putting a laminate buttplate on a hardwood stock. 

Something like this: