Is that metric hours?
The starter batteries here are generly by CCA, "Cold Cranking Amps", whereas "Amp/Hours" is generally reserved for house batteries or dual purpose. According to Autozone your van takes anything from 650 cca, to 800 cca. You can't go wrong by going bigger in my opinion, but I don't know how 800 CCA translates to Amp/Hours.
Here is what is listed for the 2005 Sprinter 2500, 5 cyl Diesel:
2 required *** 760 cold cranking Amps (950 cranking Amps) *** 100 reserve minutes. -> 3 year free replacement
Maybe you can compare that and get an idea what 760 CCA translates to.