I've recently stumbled across the following EBAY ad: item number 2570941080
They have 2 and 3 axis, Knuth DRO units with glass scales, rated at0.0001". Looks like a decent unit and the prices can't be beat for the features. $549 for 2 axis, $779 for 3 axis, plus $88 shipping charges.
It's by a company in Singapore, so before I send them my money, I wanted to see if anybody else has bought from them!