Probably something with a rail would help as you could attach different weights and also slide them fore and aft to experiment with the right feel/balance. That's what i did with my Steyr and then realised i was going the wrong way about it and actually added weight to the butt section. It helped with the stability in standing shots.

I also have quite a few of the stick on wheel weights that can be added and removed once you know where you need the weight and because the wheel weights are marked you know exactly how much.