There are one or two places in Edmonton, but I don't know if you want to travel that far.
I would definitely mail order a new scanner. There are a couple of Canadian dealers, but if you want to save money I would definitely order from the US. There are several good places, but one place I would recommend is Scanners Unlimited. I've always had excellent service from them.
http://www.scannersunlimited.com/
As for the type and model of scanner, you'll have to give more information. For example:
1. Are you monitoring trunked systems in Grande Prairie? I don't think so, but perhaps you would like a trunk tracker scanner to can track Motorola and EDACS systems for when you travel? If not, you can save some dollars by buying a conventional scanner. The risk of doing that, though, is if your local services upgrade to a trunked system, you might be left in the cold.
2. Would you like a base/mobile, or a handheld scanner?
3. Do you need to monitor digital APCO or digital Motorola systems? Not likely, but maybe you'd like to be able to monitor digital? The closest digital system to you that youi can monitor, I think, is in Calgary.
Rob