$90USD?! That must be for overnight or two day service. FedEx Ground should only cost about $55-60 Cdn. I shipped a COMPLETE bike in March from Victoria, BC to Florida for $55.98 Cdn.
A frame should fit in a small enough box to be sent via regular mail (Canada Post and USPS).
Make sure you get insurance regardless of the method you choose. UPS does not insure bicycles!
kermit