Will this airsoft gun get through customs?

I ordered this airsoft handgun and I'm worried sick whether it will make it through U.S. Customs, because I've heard nightmares about them confiscating and destroying airsoft guns they find. It's one of those hard-to-find Marushin X-cartridge revolvers. (A Colt Single Action Army) It's gas-powered. I live in California, by the way, if that makes any difference ...