Gender results b/f 20 wks, self pay and preferably with sequenom

hi all...I was wanting to find out the gender of our baby bf 20 wks but here is my situation...I can get the test through sequenom for $200 but my OB isn't contracted with them. I was wondering if I can or any has gone to just another dr. contracted with them to have the test done. I called the lab my dr. is contracted with and it is $815. I am SELF PAY so the $200 looks much better. has anyone just tried to go to any maternity specialist place to have the test done that is contracted with Sequenom? Help.