Agree with Mike.
Trimming down 38Special cases is the easy way to go.
The 360No.5 originally had a heeled bullet but I have read that some shoot well with cast .358" bullets - don't know how, but that has been reported.
I have a mold for a heeled bullet but no rifle as of yet. If you want to try some, I can mail some out to you. They are close to .375" but I will measure them again if you are interested.
Here is a picture of the bullet and a cartridge made from a 38sp case.