Crosman 1100 CO2

I have an older Crosman 1100 CO2 Air Shotgun. It worked when I got it about 3 years ago. Since that time the seals are gone or out of alignment or something, and now it doesn't work.
Does anyone know where I maybe able to get it fixed reasonably, I am on SSI and money is tight. Sounds like the rest of the US.
Thanks
stan98532
bushape1@q.com