The German army didn't directly issue ammunition for the PPSh, so the soldier would've had to find his own. It was a throw-away weapon and very reliable. However, for those captured and issued, the designation was "MP717(r)" and would be supplied with 7.63 x 25mm Mauser ammunition.
There were PPSh's that were sent back to be rechambered for 9x19mm Parabellum from 7.62 x 25mm Tokarev. Their redesignation was "MP41(r)".