Need to find a sub

mikey0013

I recently got a brand new gateway sw303 sub from one of my friends i paired it up with my 2 psw111 i love the way it sounds i wanted to buy one more gateway sw303 but cant find any online is there a website that sells them?

M50 Fronts
M10 Surround
Csm center
2 psw 111
1 gateway sw303