Another Q For the Gurus

[gunsup0331]

What Piston seal should i use? (Crosman Quest 1000x) these are the ones on JMs website that looked like they might(?) work

http://www.airguns.citymax.com/catalog/item/251485/43077.htm
or

http://www.airguns.citymax.com/catalog/item/251485/2325552.htm

top one mentions both the B18/19(which the Quest is supposedly modeled after) and the Gamo 220/440, which looks schematically identical to my gun

bottom one mentions just the Gamos.

I was going to just order a stock replacement but i figured I would try to save on shipping since JMs flat rate shipping is prohibitive and I am already ordering stuff from him.