The 830A uses different valves and has a fairly standard transformer-FW rectifier PSU section. The circuits are quite similar but not identical- different biassing arrangements and a directly heated output valve in the 830A.
I don't think a bridge rectifier would suit the 830C- it would leave the HT- bouncing around at half mains.
The manufacturer's data are both available from
http://www.nvhr.nl and the circuits can be compared regardless of language. Given the general similarity I would expect the alignment info in the English Trader Sheet data (up top) would be relevant taking into account any component reference differences from the Dutch circuits.