Never been into a Pep Boys but you can get it from Brownells for about $10. Each tin will do about 8 stocks so it is very cheap.
Regarding the Winchester stocks, they bed quite well. I use a dremmel to route out the recoil mortice and surrounding areas. It is very difficult to write about bedding especially in a forum like this and extremely easy to demonstrate it or write about it with supporting slides.
I really recommend you stay away from it if you have never seen it done as you will most likely ruin your stock though most balls-ups can be fixed, such is the benefit of Devon which in the steel version is also black and blends in with the Winchester stock well.
