More like Beer, actually, but without the -r, and only by Afrikaans-speaking people. In English, here,
Bea does indeed =
Bee. Just another example of why it would be nice to be able to use real phonetic symbols on this site, but I for one would have to do a lot of revision if it ever happens.
Bee-uh is more like the
German pronunciation, and I use it sometimes: not sure why, as my
German's pretty rudimentary and she doesn't speak it at all.