There are cheaper ones out there, I found this one (http://www.canadacomputers.com/product_info.php?cPath=710_375&item_id=061626) via a quick google search. Many of the bigger shops websites around the world will often allow you to filter results so you should try the websites of ones in Canada (outside of Canada would mean factoring in any customs fess/surcharges) and filter down the lists of tablets to ones that are about what sort of spec you're looking for (screen size, disc size, memory, etc). Once you got the list narrowed down, check each one to see if they have the connector for hooking up to an external screen, the ones that do write down the manufacturer and model and set up a spreadsheet .
The first column will be for shop, each subsequent colulm being for each of the models identified. Search online for shops that sell them models, noting down the price that they charge. Once you've got a dozen or so shows listed You'll need to finally choose which model tablet you're going for then probably buy it from whichever shop listed on the spreadhsheet is selling it for the lowest price