There is a Time-Sert kit that can repair that; it's specifically for repairing the studs the second time (Time-Sert says "for when the helicoils pull out" or something like that) but that would only make sense if you can find someone to do it for a decent price. If there are that many studs that are fucked, and you got the block for cheap, I don't know if I'd bother. You could argue both ways though, but I'd check to make sure that the repaired block was still cheaper than just buying a viable block with no stud damage from someone else. You don't want the repaired block to cost more than a good one obviously, it's false economy.

If you go the repair route, find a shop that is already equipped to do that. The inserts themselves aren't expensive but the cost of the whole kit with the tools will make your eyes water.