On most stamped AKMs, the Romy or East German sidefolders are a direct swap for the Euro-sized wooden butt. They are ugly but solid.
The MAK90s or CHICOMs have slightly thicker metal, so these same side-folders have to be ground a wee bit to fit inside the tail of the recvr.
Here is a Romy sidefolder before I swapped it onto my WASR22. Went a bit overboard on the paracord wrap... It was photo'd at a lower level than the rifle - which is why it looks so small. I blonded all the wood and snagged a KVAR blonde poly grip to give the gun the all-blonde look.