JJ,
I didn't know that the FS had a lug on the barrel, but as you say, that should not be any big deal to handle. I can't say with any certainty which stock manufacturer's mauser inlettling would be closest to the CZ. Some emails to each company's customer service might give you some answers, and would indicate which one is easiest to deal with.
I believe I would pick a stock based on style, material, and price; get some Accraglass, chisels, and maybe break out the Dremel, and have at it. Best of luck with your project. Wish I had a 9.3 myself!