have a brand new boxed TPS -L2 but no headphones.  Any idea what this would be worth.  It it totally new in the box never used, not even had batteries fitted.

I would start it off at the high side if it brandnew working and see if you get any bites, if you don't mine waiting and don't need the cash, then drop the price as time goes on. Or list it at .99 cents for a 7 day auction and let the market decide. 

The problem is, their no real set value to theses, pretty much upto what the buyer at the time is willing to pay and what you are willing to let it go for.

Are you interested in the thing? 

If not then you've come to the wrong forum.