So I just had a quick look at ebay to see if there were any broken DMG's and what I found was interesting...
Typical BIN price for a working but maybe a bit shabby DMG: ~£20-22 (+ delivery sometimes)
Typical BIN price for a broken/spares or repair unit: £30-40 (sometimes even more!) + insane delivery!

W. T. A. F.
I guess the decent priced ones get bought instantly by sudomoders

I'm going to stick to car boot sales or maybe even my friend in Japan... or just use repro shells for any future ones...