i got that seat off ebay. i basically lucked out. a new Brooks saddle goes for around $130 to $300 depending on style, and used ones in good shape go for $60+. the one i found was coming from the netherlands, and shipping was 25 bucks, so it was $26.25 total.
it's a B66S. it's a ladies cruiser seat, so it's fatter than the B66. it's smaller than a regular fat cruiser seat, but it's super comfortable. most comfortable seat i've ever owned.
when you first get one (especially vintage, dried out ones) they seem really hard, but they break in after awhile. i used "neatsfoot" oil on it, the same stuff for softening baseball gloves. it darkened the leather quite a bit, but i don't care about that, and it really softened it up.
if you do find a seat like mine, i suggest getting a cable lock, and running it through the seat springs, too. people that know what they're worth like to steal them. and by taking your seatpost off, it takes two seconds. then, not only are you out a seat, but you've got a very uncomfortable ride home.