There are always the Smith airlights in titanium or scandium (if you win the lottery). These are "carry a lot and shoot a little guns", and you can practice with low power .38. Honestly, its an across the room gun. I may get contradicted, but if you're a decent shot and shoot it enough to know shot placement with that weapon and your SD load, most of your practice can be drawing and firing with snap caps. Seriously, you're looking at a 7-10 yard gun tops. I wouldn't sweat hearing damage or recoil in SD. You'll never notice till its over, the cops will own the gun anyway, and a little ringing in the ears beats the alternative. Just my .02.