I think MAS 49/56 has a grenade launcher that has to be removed in CA, I'd like to have a MAS 49, missed one around $200 in 2005. If I see a MAS 49/56 I will let you know. I'd stay away from the Century Arms converted .308 versions.
As with most milsurp items, if you miss buying them during the time they were imported, they tend to get expensive later.
French milsurp is not particularly popular though compared to US items so you may do ok.
Saigon, I reccomend you check out the sale forum and French forum at gunboards.com