Ahh, you have a trilogy. You have to get a trilly pump kit, as the pneumatics and body are arranged differently.
That sort of narrows down your possibilities, but the heaviness of the pump stroke comes from more your internals, not your pump kit. Normally i'd say go with CCM every time, but they don't make a trilly kit. I think
these ones are the ones most MCB'ers recommend.
There is an LA Hitmen signature kit on there too, but the only difference is a hitman modded handle and a hitmen logo lasered on the side.