If you like, you can skip directly to where you can buy this part.
We sell good, original BMW, used E30 glove compartment units. The price is $40 plus shipping.
At the time of this writing (spring 2013) a new original-BMW replacement unit is priced at close to $250 from Pelican Parts (a wonderful vendor whom I personally buy from, and endorse, though I don’t anticipate buying this particular part from them any time soon, personally).
Allegedly the BMW dealer charges more than $350 for a new original-BMW glove box unit.
It’s probably safe to say that our used units are price-competitive.