There is no best place to buy a gun sear since each state sells different guns and ammunition. The best options might be a local gun store, a sporting goods store, or a pawn shop.
Your local gun shop.
AirsoftGi.com ------- Airsplat.com -------- hobbytron.com
Airsplat or pyramydair
http://shortyusa.com/index.html?RID=4328
Check out http://www.gunsinternational.com/ Gun Classifieds You deal direct with the seller. Best site I have found and I have been at this a long time.
sear
There are many place to purchase a soldering gun for home use. The best place you can buy a soldering gun for home use is Office Depot. You can also find it online at Amazon.
The sear is the part, usually moved by the trigger, that releases the striking mechanism, so that the cartridge is fired.
If you are asking how to fix it: Unfortunately unless you can glue or seal it it, the gun will not work without the Black sear pin. You may have to buy a new receiver half.
The best place to get shot by a gun is the Legs, Arms, or Butt No just the arms.
Well at a gun store you know well like I know SEX my favorite!
That is the part which releases the hammer or striker to discharge the gun.