Henry Sprout

Does anyone know if/where anyone would be selling a performance chip for a 1987 5000 Turbo Quattro? I've been looking around for a while and the more I look the more I see people raving about its wonderful affects on performance but nobody seems to know where anyone is selling them. Do I have to just load code onto a blank chip and replace, take it to someone to do that, buy a pre chipped ECU, or track down the ellusive QLCC? Thanks for any help!