Rob, do yourself a big favour and just replace the axle.
I bought a brand new 3,500lb axle with 5 on 4.5 bolt pattern built to my specs complete with new lug nuts and U-bolts from Standens for the grand total of $197.00 including GST.
I phoned the order in one morning at 7:00 and an they called me the following morning at 7:30 advising it was ready to pick up. It took me an hour to swap it and that including painting the axle.
Oh yeah, the new axle was equipped with E-Z Lube hubs for easy servicing.
You can order it with a wider WMS to WMS to accommodate the the additional backspacing of the typical Jeep rims.
I don't know what the adaptors are worth but I'd think at least 50 bucks a piece so your half way there.
Vince