D0VE-A blocks and D0VE-C heads seem to be the most preferred blocks and heads among enthusiasts. For the most part, the D0VE blocks and heads were utilized primarily in the 1970 model year vehicles only, although you might find them in a handful of 1971 vehicles as well (most likely the heads and less likely the block).
The heads are of the higher compression variety for factory iron heads, and the blocks are a 1-year only thick-main webbing design that facilltates converting the block to 4-bolt main caps, so people pay a lot for the D0VE-A blocks. The fact is, though, that any standard-web 429/460 block can usually handle more HP than most people build for, and also there 4-bolt main cap conversion kits for these blocks as well these days. But the parts you ahve are still the preferred parts.
In regards as to whether it is a 429 or 460, the best way to determine this is by following identification instructions as outlined HERE