$475 for an LP D44 is nuts. Honestly, and I ran a Waggy 44 for years quite happily, I'd stick with a 30 if I were to do it over again (indeed, I DID in my WJ). The LP44 might be marginally stronger at the R&P, but that gain in size is negated by its being LP, as compared to the stronger HP design of an XJ D30. It has stronger 30 spline shafts, but how many jeeps have you seen on 35's with 27-spline D30's and how many are regularly breaking shafts? not many. Same ujoints so no advantage. Waggy 44 has 1/2-ton chevy brakes, which work well and parts are cheap, but for the costs of fabbing to put it in, you could do a WJ swap on your D30 and end up with comparable braking.
If you need a 44, get HP, otherwise, build the 30 a little. (IIRC, there is a narrowed HP44 in the local classifies for cheap...).