Years ago when pin shooting, I used to buy 230GR .38 bullets from as I recall , the Butte Bullet company. I dont have any idea if they can still be had from anywhere, or if the Butte bullet co. is still around. Thats as close as I know of to what I think it is you are wanting.
They need to be loaded in .357 cases and fired in a .357 Mag revolver however as the lengh when loaded it too long for a .38 special.