I found one so far but it seems like a pretty rare thing.

I'm confused as to why anyone would be interested in any provider who offers BBFS.  Walking into an STD trap if you ask me, not to be rude or vulgar but that's what it is.

It's not only UN SAFE but it's  DISGUSTING.  Any provider practicing this way should be reported to the community...IMO honestly...it keeps those of us who are safe, SAFE.  I wouldn't want to see anyone who has seen a woman who provides BBFS...that's just gross eeeek!!

Yeah, that scares me a little bit (and by a little, I mean a lot). I'm already paranoid and get tested, and that's with me fully covered! Sex is better bareback, but that's not something I'd like to risk with a provider.

BBFS is strictly YMMV situation.  I know of one very popular provider who if she likes you will do everything BB.  One suggestion, usually it occurs if you have been seeing a provider for a while and you must be prepared to have your up-to-date HIV and STD medical report. Since most reputable providers get regular check-ups you should require the same of them.  Afterwards, wash throughly.
But, as other commentators have said, its a dangerous way to go and one must be conscious that the hobby is a community.