This is a great company for WW2 reenactors to be able to get "automatic" firearms without having to get truly automatic firearms with the BATF hassle, transfer tax, and prohibitively high expense. But alas, if you're from Canada, then it's not an option.
WWII Guns is a very interesting site, and one that definitely makes one get itchy to order one their fine replicas. It sells a mixture of Airsoft (guns that fire a plastic BB) and cap-firing replicas. The caps in these are very similar in appearance to an actual blank shell, and have a similar report to an original. Reenactors would definitely prefer the more realistic cap-firing guns.
I suggest surfing this site thoroughly, and playing the product videos, which give you a better understanding of the products offered. In the US, you need to be careful about this site. It's great for obtaining a cap-firing replica of an automatic, like a Thompson, MP40 or PPSh-41, but the bolt-actions/semis; M1s, K98s, and Mosin-Nagants; are comparatively expensive. You could still be way better off buying an original, so shop carefully.