The silencer is illegal. According to the ATF, if it reduces the sound signature a certain number of decibels, it's illegal. They have confiscated Paintball silencers because they use the same technique to silence the report of a marker that "could" be used to silence a firearm. The ones being sold by those companies are cosmetic.
Will the ATF come raid your house for it? Probably not, but according to them, it is illegal.
Nice gun! I would think a remote would be easier as well.