hello and welcome to the old pmi forum.
the only o-ring that needs to be the right one is the hammer o-ring. you can use tank o-rings or onther black o-rings for the bolt to have the bolt seal. you may want to go over to boss paintball products and pick up some o-rings. (he sells them one each or in a pmi repair kit.). pmi now uses blue colored o-ring for the hammer.the ones for spyder are red and not the same size.
Does an ursine quadruped void wastes in an arboreal environment?