DDR T-55’s came from Czechoslovakian or Polish production plants.
This one looks to be the Polish(Bumar Labedy) version- it has the Spares and Accesoires Box mounted horizontaly on the left side of the turret.
A typical DDR feature, that was present on all NVA tanks(NVA here stands for Nationale Volksarmee, not for North Vietnamese Army) , are the railroad transport chockes, placed above the exhaust.
Edit: On the other hand- I doubt the RMSh tracks, visible in the boxart, were commonly available for DDR T-55’s in the 1960’s.The Soviet Union had a vast T-55’s fleet, that needed the new tracks, and NSWP had lower priority.
Cheers,
Angel