The MFP radios are obviously mock ups, and the originals were just built with a fairly random assortment of electronic components. Sam Costanzo has done a great job of copying the radios, as can be seen by the pictures on this page. Sam can be contacted through the email form at the bottom of this page.
Sam has some more pictures of his radio online in an album at Yahoo, and also at his web site, which contains some pictures of the repica car he is building as well. The picture below shows one of Sam's radios mounted in his car.