I have the 4 track r2r deck (A-3340) that is of the same series as yours, which TEAC put out in the 70's. I also have many of the complimenting accessories, including a Model 2 mixer, the meter bridge, the aux mixer, and a few other random pieces. That being said, I'm not really sure of their value, but I know that finding parts is extremely difficult, should something go wrong with the unit (most likely, it will. These units are NOT reliable). There is definitely some collector's interest in these units, FWIW; I have never looked into selling mine so I have no idea what kind of value they hold.
BTW, I have used my deck in the past simply as a dedicated tape reverb/echo for vocals on multitrack products and it sounds AMAZING.