The unit and tapes inside appear unused. The tapes are still all shrink wrapped.
The history of this unit (based on the receipts inside) are as follows:
Shipped 03/05/1990 to a woman in Auckland as part of a study course called "Personal Computing" by a company called "ICS Australasia"
Probably these guys? http://skillscentre.com.au/about-us/
Unfortunately while the tapes are present the cassette unit other course material is missing apart from a list of modules covered.
Clearly they didn't follow through with completing the course!
up as originally shipped, and the plug doesn't have scratches on it, I scored a c64c setup like that last year, the cables appear to be folded and tied as it comes new and there where no scratches on the plugs so it left it in the box as it is, its to good to take out 
and it may have never been used!