Rising Storm Tommy Gun

I can't buy the rising storm tommy gun in-game, even though rising storm is installed in my library and i actually played it today,even after the "download red orchestra 2 for free and keep it forever" thing, not to mention, i used the tommy gun yesterday, and now it says it's dlc for me. I tried restarting steam and verifying the cache,with no success. would love to get answer ASAP