Was there any shipping fee in the listing? There is a separate tab for Shipping and Handling.
Was there a shipping fee to Canada in the Shipping and Handling? If not the seller is allowed to charge whatever he thinks is fair to get the item to you promptly and securely.
If the seller refuses to send you a Mutual Cancellation, which is the friendliest way to end a transaction, and should include both buyer and seller leaving positive feedback, he still has the choice of opening an Unpaid Item Dispute, which will give you a Strike and make it harder for you to bid on eBay in future.
The colour on monitors will vary. I don't think you can blame the seller for this, especially if the colour varies from picture to picture. That's just the graphic interface. Or possibly gnomes.