I thought about that also, but I wasn't sure whether the earliest DSs had the wider grip or not. I have no first issue DS, only later ones, and no PPSs. In any event, it's very probably a PPS with a cut barrel.

I recently ran across a PP snubby in .38 S&W/New Police (basically like a DS in .38 S&W, but with a PP frame and barrel), it looked authentic but I didn't know enough about PPs to take a chance on buying it. BTW, there were also a few DSs made in .38 NP.