Rebuild (seal) kit for Powermaster - such a thing?


'87 GN (for sale)
My Powermaster system seems to be working correctly, but the master cylinder seals are leaking, and possibly the pressure transmitter or-rings. Since the rest seems to be OK I'd like to just replace the seals for now. I have checked with some local auto parts stores, and also in a couple GN catalogs and haven't seen a kit. Does anyone know if a seal kit is available? If not, I can probably source the orings and seals, it just means more downtime while I disassemble the unit, measure the seals, then visit a local o-ring/seal shop to get what I need.
Thanks in advance,

P.S. I'm not interested in replacing the Powermaster with a vacuum diaphragm system or a new Powermaster.
Yep GM PM rebuild kit...#18038510...get one from discount GM dealer or better yet GMPartsDirect...with shipping $43.54...
I belive Hank Terry sells these kits too. I know he's the "pump man"
Thanks guys....
but who is Hank Terry? I'm brand new (10 days) to the GN world, so I haven't heard all the names.
I have been to Conley's shop here in Houston, and got catalogs from Poston, Kirban, and ATR. I'm working on it....ha ha