Hit the Yellow pages and start with the entries for "Foundry Supplies" or "Refractory". In Edmonton, I'd suggest a phone call to Inproheat, and start from there.
Those would be the guys selling supplies to about anyone that casts on a large or small scale.
You want to ask the sales guys there if they can put you in contact with a Foundry, not a forge. Foundries cast, forges beat metal into submission after they make it hot.
Distance is gonna be an issue, so where you are located would be good info.
I know a couple guys in the Edmonton area that cast bronze occasionally. One fellow SE of Edmonton that casts some iron, but probably not in quantities enough to fill the mold (EE, a while back?).
There is a fellow name of Stewart Marshall, in Washington state that casts both bronze and iron cannon blanks, which he sells, as well as writing several books on building and using a cupola for casting. If you are in his area, he may be worth tracking down.You can dig up some info on him, online if you look.
Cheers
Trev