Is It Possible To Buy Canadian First Day Covers But Just The Envelopes?

I really like some of the designs from Canada Post and the First-Day covers. White envelopes are so boring, but when I checked their site, they only offer a few types of prepaid envelopes.

1. Does Canada Post sell the FDC envelopes only? (Didn't see on their page)
2. Is there a Canadian company or individual that makes nice envelopes that I could simply add my own stamp to?

Might as well make letters more interesting.

Tom, have not known them to have sold their cacheted envelopes seperately.
I do believe the printing company gets an order and prepares the stamps, souvenir sheets, and does all the covers for them also and just sends it all to Canada Post for distribution.
Philatelic material ordered from website does not get shipped from the Philatelic centre in Antigonish anymore. Antigonish is more or less a call centre now. It all now comes from a warehouse in Ontario.

I guess the envelopes would be too fancy and might mess up the sorting machines. This is probably why the pre-paid ones they do sell as much simpler than the commemorative versions. Thanks.