This guy on Naxja has a few things for sale, including a Solid D30 diff cover still in the box for $60. He's in Southern CT. He also has a XJ front driveshaft for $30. Might be a good one to build as a spare for all of us with YJs and TJs with SYEs.
http://www.naxja.org/forum/showthread.php?t=1007926