How big of rubber are you gonna run?
Since the 465 doesn't have O/D I'd just go with the more common 4.10's rather than waiting to find one with 4.56 gears in your price range. The 4.10's will help keep the rpm's down on the highway (especially since diesels are lower revving engines) and the cummins will have plenty of torque to get you moving. The 465 has the granny low 1st so the 4.10's won't be too high for crawling either.
Just a thought anyway.
'84 CJ-17: 17" stretch, locked Toy axles, 5.5" lift, FI, AX15, D300 w/twin sticks, boatsides & junk.