Airsoft Canada - KJW GBB M4

I was in the middle of a game last Sunday, when my M4 suddenly started spewing gas from the mag. After I ejected the mag and looked for a problem, I noticed some black pieces sliding around in the lower receiver. So I wandered over to my car, opened the rifle up, and pulled out the charging handle and everything attached to it. That's when I saw this:

http://i90.photobucket.com/albums/k2...e/IMG_0259.jpg

Once I pulled the piston and cylinder apart slightly, I got a better idea of the damage. I also noticed some damage done to the piston ring, which you can see in the following picture:

http://i90.photobucket.com/albums/k2...e/IMG_0263.jpg

Having only bought this thing from buyairsoft just over a month ago and only being in five 4-hour games (5th game was actually only about 2 hours, gun broke halfway through), naturally I'm pretty irked. I've tried contacting them, but never got a reply (tech request was sent on the same day it broke).

Now, I can find a replacement for the piston ring easily. It's the cylinder that is causing me grief, as after extensive Google searches I don't have any idea where to get an aftermarket version, let alone a stock replacement.

So if there is any GBB Gun Doc near Cold Lake, or if anyone can send me in the right direction, that would be great.