You could probably find that stock at a number of places and for relatively cheap. Lowe's, Home Depot, Menard's, Walmart, Kmart,and just about any Mom and Pop Hardware Shop. Maybe a gas station or two if you live in a place that snows regularly.
The two choices you have to make are between plastic and aluminum, depending on what kinda weight you want to be hauling around and what durability you want to have.
I have a plastic one on my AK, it seems to be working fine. I am kinda envious of the one that's shown. While being a little short, it's OK because I need a shorter stock because my bubble wrap and styrofoam block protective vest makes it too long of a pull to be comfortable.
As an added bonus you also then have a nice long baton that detaches to be able to bludgeon the people you cant hit with the rifle. Great for the CQB environment or if your kids get out of line. For around 12.99, you can't beat this stock, I'd swear by it any day of the week and twice on Sunday.
Good shooting and I hope this helps in your quest for finding a great stock!