Puzzle 129, 134, 139, 144, 149, 154, 160 are already solved, this means that this puzzle is rigged, but anyway, is it harder to solve puzzle 66 than mining a block?
I just wonder, why did you start with 129 and not 66 or 67? And what do you mean by this puzzle is rigged, how exactly is it rigged?
To answer your question, we can't really compare mining with key brute forcing, but I'd say if you spend 3 bitcoins to rent GPUs, you might be able to solve #66 and grab 3.6 free bitcoins, but I'd wait for experts to calculate the exact cost.😉
Ps all puzzles from 161 up to 256 are already solved, dis rigged puzzle!😅