Not at all. Since you can decide how many bloodhunters to use, you can push your blood slave income up pretty high.
Three bloodhunters in a province are likely to bring in ~15 slaves a month. If you've got 7-8 provinces being hunted, 177 is only a couple of turns.
I think that with one hunter per province you can get that in two-three turns if you have 7-8 provinces being hunted. Obviously depends on the special site freç