My back of a fag packet calculation put it closer to 400 dT.
A quick Google shows the Roci to be about 46m long and from various pictures seems to be about four times longer than it is wide:
11,5 x 11,5 x 46 =6 083,5m3 / 14 =434,536 m³
The grognard in me likes 400 dT as it's the classic SDB...