Seeing that that's a cassette 4-track, the only way I can think of would be to have it transferred to a CD professionally.

You can usually do that at shops that do DVD transfers.

Good luck
-Benji

Or you could mix it onto a CD burner

4 track to computer

I dumped some stuff from my 4 track with a Creative SB interface box. I got it from an office supply store for about $45. It has RCA inputs and a USB into the computer. I just run out of the RCA outputs from the 4 track into this, plug it into the USB port, and there you go. I think Edirol makes one as well, but its about $70.