I shipped a HEAVY dressage saddle from MA to Ontario for right around $60. Insured, tracked, etc. Got there in....less than a week? It was last year so I don't quite remember, but it was quicker than either I or the buyer was expecting.
I ship all my saddles in-states for $20-$30 with USPS, so it wasn't that out of line to get it across the border.