昆山 Kunshan is about 30 minutes from Shanghai on the way to Suzhou. I　was there about a year ago and there is a large red light district along the southern bank of river that runs through the middle of the town. There are lots of Taiwanese businessmen in this town so there are plenty of opportunities.

I don't have any information on prices since I was with a normal girl that night, but Kunshan is a small town so I don't think it will be too expensive.