Another issue might be the stock's length of pull. A too long stock will beat you up much worse. I have a Mossberg 590A1, that with the OEM syn furniture was both too light & the stock too long. Beat the bajeebus outta me.
Bought some NOS wood furniture for the extra weight (& look). My SKS fits me like a glove (I'm built like a gorilla at 5'7" & 46" chest), so I measured its LoP & cut the Mossy stock down to that length & added a LimbSaver pad.
Huge difference. Much more comfortable to shoot.
I'd be hesitant to hack up a CZ stock in my garage, but if the stock's too long, you might look into having a good 'smith cut the stock down & fit a good pad.