What’s the going rate for one these days ?
Got one with shafts sitting in garage that I’m never going to use.

At a very big guess over 200 pounds
G

My perception is the home build market is disappearing & what hasn't disappeared has moved onto using MX5 or BMW diffs. 10 to 15 years ago i think it was worth a lot more than it is now unfortunately (says he with a 7" diff under a workbench).

I have the 3.14 without an LSD. Could the internal LSD be swapped over?

Not certain but the crown wheel & pinion may fit the lsd.