I've ordered gear from RRS into Canada, including a tripod, etc. There are no Canadian distributors. When ordering:
1. ONLY select shipping via USPS shipping. NEVER, as in NEVER, EVER, UPS (or to a slightly less evil extent, Fedex). If you do, well, I think you've been there before from reading your OP.
2. You just pay HST/GST when pick up at post office. That's it. No duties, etc, etc. as with UPS and their infamous "open hand" policy at the front door (or 6 mos later via the mail) BS.
3. USPS is pretty quick. Never had an issue (knock wood).
BH - 99.9% of my purchases. HST deducted at source, NO BS fees, fast, (very) cheap Purolator shipping and no questions return policy. For me, they're the gold standard for buying photo gear be it from US to Canada or buying from a CDN retailer (for me, only when no other choice).
You can also check B&H's used department, they sometimes get RRS gear in.