Puffie40,
Me being the curious type and enjoying searching for possibly elusive parts, a little web searching located this
GM# 3812762 2 Speed vacuum shift control that looks exactly like your broken control piece.
A further check of
GM parts wiki, a search engine for GM part numbers shows this control fits 1955 2nd series and later Chevy 2 speed rear axles. Should be the same as your 2 speed, but I couldn't find an actual GMC parts book to confirm. Perhaps one of our resident GMC guru's can chime in to confirm or not?
Unfortunately that eBay seller indicates down in the ad description that they ship only in the USA. A fellow Bolter may be willing to help you out in acquiring and re-shipping to you in BC, or maybe you could get lucky and find a fellow BC Bolter that has a USA address for shipping already established???
FWIW, that part number was replaced in November 1990 with GM# 2428149 and is also listed under the original part builder as Bendix# 2501124. Perhaps you may be able to locate one through a Canadian parts source???
Anyhow, hope some of this info may be of help to you. Good luck in your search!
