No silencer is going to actually "silence" your airsoft gun since the sound is coming from the gearbox, not the barrel. But a good place to get a mock silencer would be Airsoft GI and Evike.com
It depends, dose your your sniper have threds? Type airsoft sniper silencer on Google and you will get something.
it depends on the scar that you have. if you have a d boys or agm scar or echo 1, they will all have a 14mm CCW front flash hider. in that case, you can just buy a mock silencer and replace the flash hider. or you can buy a quick detach silencer which is what i use. you should check airsplat.com for silencers, they have a really good selection.
put a silencer on it
well depends how cheap i got a great electric abs plastic and metal mp5 that was about $100 and i have a g36 metal 500 fps electric w/ silencer and laser and grip its good and right now i am buying a fn p90 metal electric for with silencer for about 150
you just buy the silencer
Anything is possilbe with enough money and the time it will take to jump through the NFA hoops with the BATFE. Airsoft rifles do not create a loud 'bang' as does cartridge rifles. In fact there is almost no noise. That being said, WHY would you put a silencer on any airsoft gun ???
Their are not any airsoft stores in Massachusetts. (That i know of). But i buy sll my airsoft gund either from the following; airgundepot.com;airsplat.com. 2 very good sites.CrattleCrie
depends on what you buy and if you can fix it
These are the top 3 for me: Airsoft GI Ehobbyasia Evike/airsoftpost
hitguns.com airsoftgi.com evike.com
ASGC in Parnell
If the flash hider is removable then you just screw it off and screw on a silencer. If the flash hider doesn't come off there is currently no good solution other than modifying both the flash hider and a silencer to attach and be secured on the gun.