I only have "Primal Colors" which sounds like a collection of early stages of The White Album.

Granted, I'd love to get a taste of unreleased Beatles circa 67-70. Any recommendations?

a lot of the boots go a bit nuts with 1700 takes of each track, etc, and you have things like the complete AB sessions, which is everything they recorded in a month for the get back video

i'd suggest looking for the purple chick releases as those are pretty good. there were also "alternate..." albums with different mixes/takes making up a new version of complete albums, like abbey road, the alternate versions of abbey road are pretty good. the white album esher/accoustic sessions are also pretty good. there was also the peter sellers white album tape, i think the primal colours is a mix of various stuff

if you have a google you might find some beatles fan sites that list the best boots. some of them are amazing quality, apparently someone borrowed and copied a lot of the tapes from abbey road so the bootlegs have perfect sound, some actually sound better than the original edition cds