I don't know how much he charges, I think he did mine for free when i bought one knew. Dave Fedderly is a real nice guy, and pretty flexible, I'd be willing to bet that he'd do it while you were on tour and then ship it back to you later(if you were willing to risk shipping a horn cross-country).
How are the vented valves? I think i should get that done, but I have no cash right now. BTW, what's your tubenet SN?