only the breech o-ring is different between different calibers of the same model. the sapsan o-rings are different than than the kozak. I have the old kozak drawing and it is in Ukraine but the numbers are still numbers and it is pretty easy to get o-ring sizes and screw sizes from the drawing. you do not need to translate to know which are set screws from cap screws
I have taken both apart and the sapsan is a lot more complicated machine than the Kozak. I have tuned my Kozak down , set the reg to 100 bar and free flight my hammer spring by clipping coils. my sapsan sits in pieces, long story 2 yr long, lost interest due to due to world in up heavel. I need to contact Andrey and request some parts to get her going, she has been a dead horse every since I got her from no test it out Joe, I should have returned it, but I like to fix stuff. the american importer is the weak link in my opinion, he should have all the parts on hand or he is just in it for a quick turn on his money, just a retailer that fails in the importer role. you can buy spares from other gun importers. I really like my little Kozak compact and was sad when I learned that Joe got the import business
