There are enough on AW in the vicinity eg Liverpool and Chester as well as a few on the Wirral (a couple of girls alternate between Liverpool and Wirral. At least with AW there is some chance of knowing if they do bareback or not, adverts elsewhere are short, if you phone up and ask if they do bareback only the barebackers will answer that, the others will block you.
The girls that don't advertise don't want their name put around by their regulars.