Hello!!
Despite your posted intentions, I believe that mixing down and recording to your 'puter into Wav files @ 16-bit/44.1kHz/stereo format is the best option, as you'd then be able to lay your mixes (wave files) out in sequences and burn CDRs from them,... which is a vastly superior reproduction medium than cassettes.
The accessory you'll need is a 1/8"-to-RCA stereo Y-cable adaptor, which is a common and inexpensive "Radio Shack" type of item. First, develop your mixes to their optimum on your regular monitoring system. Then, cable up from the Line Outs of the 424 to the Line-In on your soundcard. Eh,... you'll need software that records into stereo wav files, and you'll need other software that sequences wav files into songlists and burns cds.
Sorry to take a different twist on your question, but I believe this is a superior sounding and sturdier duplication solution than cassettes.
Otherwise,... I'm partial to vintage 80's-90's Technics stereo cassette decks. I have an RS-B555, & a RS-BR465, but my all time favorite is the RS-955. You could also do well to get an RS-B50, an RS-B78, or an RS-
M240.
Aye!
