Here's a few (what seem to be) reputable performance shops that will tune GM PCM's.

Ontario:
http://www.mgscustomtune.com/index.html
These guys garauntee their tunes, or they'll retune it for free, and they'll pay shipping.

Alberta:
http://westersgarage.eidnet.org/index2.htm
http://www.torkwrenchtuning.com/contactus.htm

Although not as cheap as PCM4less, or wait4me, it may give some the opportunity to make their way out to the dynos.

Please add some if you know or find others north of the border.

Any way this could end up as a sticky if it meets the "sticky standards"?