Hog Island Boas are AWESOME animals, relatively inexpensive and yet a BIG, BIG female would be 7ft or less. My five year old female is about 6ft and close to the diameter of a baseball. Males stay even smaller. Just make sure you buy a pure hog, some of them are crossed with BCI or even BCC sometimes and as a result , those specific animals get a little bigger.
You're suggesting looking at a smaller boa....I can't believe no one said "Hog Island" yet.
Consider it. I LOVE my girl.