Here are all of the options for a 2004. I assume that is what year you have.
Sport Trac, AM-FM-CD6-MP3, (ID 4L2T-18C815-FA), (Adrenalin pkg)
Sport Trac, Amplifer, (ID 4L7T-18C808-AD)
Sport Trac, AM-FM-Cassette-CD (sgl disc), ID 5L2T-18C869-BB
Sport Trac, AM-FM-CD (6 disc, in dash), ID 5L2T-18C815-BB
Sport Trac, AM-FM-CD (6 disc, in dash), ID 5L2T-18C815-CB
Sport Trac, AM-FM-CD6-MP3, ID 5L2T-18C815-BC
Sport Trac, AM-FM-CD-MP3 player (sgl disc), ID 5L2T-18C868-BC
Sport Trac, AM-FM-CD-MP3 player (sgl disc), ID 5L2T-18C869-BC
Sport Trac, AM-FM-Cassette-CD (sgl disc), ID 5L2T-18C868-BA
Sport Trac, AM-FM-Cassette-CD (sgl disc), ID 5L2T-18C868-AB
Sport Trac, AM-FM-Cassette-CD (sgl disc), ID 4L2T-18C868-BA
So I did a search of the top listed item. Here is what came back...
(Not to good of a selection in my opinion)
Year
Part
Model Description Part
Grade Stock# US
Price Dealer Info
2004
Radio
Ford Explorer 05G020 $200 Deluxe Auto Parts - KOLT USA-TX(Corpus-Christi) E-mail 1-800-654-3589
2004
Radio
Ford Explorer 4L2T18C815EA A 40713 $150 Butler Auto Recycling USA-FL(Pensacola) Request_Quote 1-888-441-8010 Request_Insurance_Quote
2004
Radio
Ford Explorer AM FM CD,MSSG KNOB,4L2T-18C815-EA OD0025 $150 Sierra Auto Recycling, Inc. USA-CA(Ridgecrest) Request_Quote 1-800-346-8733 Request_Insurance_Quote
2004
Radio
Ford Explorer AM FM CD,4L2T-18C815-EA,MSG KNOB OI0001 $150 Sierra Auto Recycling, Inc. USA-CA(Ridgecrest) Request_Quote 1-800-346-8733 Request_Insurance_Quote
2004
Radio
Ford Explorer SINGLE DISC 00050543 $137.5 Bay Auto Parts - QRP Partner USA-WI(Green-Bay) Request_Quote 1-800-229-2886 Request_Insurance_Quote
I'll put it out into a bang list and see if anyone hits on it with a defective radio...