The mylar substrate would probably be the easiest. I don't know if anyone's still making audio tape, but the coating equipment might be the same. I don't know how to find the proper stuff for the goo, however.
ATR Magnetics (www.atrtape.com) and others still produce audio tape. They have normal consumer-style stuff up to the 2" reels. Not sure if the 2" stuff they sell will work on digital machines like the Sony DASH machines.
Cassette tapes are kind of back a little as well and apparently there are duplication houses for them again.
-- : Ethan O'Toole
