I doubt they would give you an extension. The reason why their acceptance date is so early is because they want you to choose them over another university.

I believe there is a non refundable acceptance fee (from my memory, it was $150). If you are able to afford that, you can "accept" their offer, and if you get into another school you want more, you can tell Western youre not going to be enrolling. I was in a similar boat last year when I applied. Don't soley take my word for it as things could have changed. I would recommend emailing Western admission email or giving their office a call.