Found a really good deal on a MKII heavy barrel with RB trigger and BSA Platinum 8-32x44 scope. I want to put a different stock on it in the future, because the stock now is a benchrest thumbhole. What info do I need from the gun to know what kind of stock I can put on it? Looking at a BV, or the Boyd TR look-alike. Pic I have shows a hole in front of the loading port, and what looks like 2 piece bases.