I honestly do not know if +P would offer anything except muzzle blast in such a short barrel.
Speer makes a 135 gr. JHP Short Barrel
38 Spcl. +P round especially for snubbies. The big problem now is finding some! I really want to give It a try in my LCR. For now I'll be content with the 158 gr.LSWCHP +P "FBI load" rounds I have.