Hey Michael, I'm new to both this forum and the HT thing but in doing research towards replacing my 20 year old TV later this summer with a renovated and equipped HT, I came across your situation.
Like you, I'm in Canada and find the difference, on certain components, to US prices verging on criminal.
Re. the Onkyo 805, it too is on my radar and I was disheartened to read that eCost will not ship to Canada. FYI, I came across a post from another Canadian who bought one through an eBay storefront. It seems I can't post a link for you because I'm too new to the forum but go to Ebay and search for TX-SR805; the seller I'm referring to is called E Warehouse and sells them new & boxed for about $620. If you're not adverse to eBay, it looks like an alternative for a new 805 at an attractive price.
I have no previous experience or any relationship with this seller.
Peter