I was in the same situation about a month ago, I've had a DSN cased Little Hero 112 for a few years and wanted to replace the case/crystal since they were really beat up.
I went with a 111J case, 005 Crystal and 111J caseback. Im going to reuse my LH dial/hands, LH movement and the thick crown. I also think i'm going to have to use the 111J CG (instead of my LH CG) to stick with the "J" series and a rollerball lever.
Plus I just found out if you want to use a non-rollerball lever with these new pam cases you need to change out the hex crown tube (see link), which I dont want to get into right now.
http://repgeek.com/showthread.php?t=136950