Most bite valves I've had are pretty much universal, the tubing is usually about the same size from one brand to another so you pretty much just need to jam the barb fitting in. If it seems like it's a little loose you could probably throw a hose clamps on it if you were really intent on not buying a new hose.

At the other end of the hose the fitting to connect it to the bladder may be another story, that definitely changes from brand to brand and over time as they roll out new models, so getting a new one to fit may be impossible.

ah damn, that sucks. thanks for the answer!

Huh? I've had water bladders from all of the major brands, and the bite valve was removable for cleaning on every single one.