Replace your old style o-rings with the new x-ring. They are shaped like an X instead of an O as shown in the pictures below. The benefits to having x-rings instead of o-rings are that the x-rings cause less friction, and provide a better sealing interface. Instead of "rolling" and breaking the seal with ordinary orings, the xrings do not move and continue to provide a flawless seal. Also, because of the shape, the xrings do not need to be pushed against the inside bore of the marker as much as an ordinary oring. This reduces friction so it increases efficiency. We have found that you will need to make sure to keep these x-rings lubed. They need to always be nicely lubed so the maintenance may be a little bit heavier than regular orings. This is however just fine because of all the advantages it provides over ordinary orings.
The Apocalypse Custom Paintball X-Ring is older, so while it may be available used and in a few cases new, it is not commonly available anymore.