If you look at the ad boards you'll see girls are still setting up in KoP and Plymouth Meeting in the Western Suburbs. You're right that there has been more LE activity there, including an announced bust recently.  But discretion and screening are your best bets to stay safe.  

Downtown near the convention center is also a good spot, as is the airport. Each has their benefits and each will attract a different set of guys.  There was a thread not too long ago on each of those areas. Maybe try and search for it. Good luck!