I didn't get mine from these guys, but you could try them. Also, I see the DA models all over amazon; just need to weed out the plastic LX ones.
Jewelry Tools - SEP Jewelry Tools of Chicago, Inc.
Also, be aware the the higher power ones (like the DA10s I have, 3.5X) have a pretty low focal length (~4") which makes soldering, etc. a bit challenging. I've meant to get another lower powered lens plate for mine, but just haven't gotten around to it yet