Instead of miniatures, I use counters. The following link is for a PDF of over 170 counters to use in the Burnt Offering Adventures. I think that all the monsters are included, even a few spiders for summoning.
You just have to print it on a WHITE FULL SHEET LABEL (Avery 5165/8165) ; apply it on cardboard (cereal box) and finally, take out a good XActo and cut the 170 counters.
I hope you will enjoy that tool as much as my players do.
Download here