I think building a front D44 is way more expensive than building a D30 - I just built one earlier this year. I've never seen a front D44 for $200-$400. They are usually closer to $1000 in my experience. Either way, the axle is the cheap part.
Ford D44: $800
TnT truss kit with all mounts, shock mounts, etc: $500 (this was cheaper than piecing together all the upper and lower mounts, trackbar mount, shock mounts, truss, etc)
Welding on the truss: $200
New Gears: $250
Master install kit: $150
New Yukon air locker: $800
Gear install cost: $400
New high arm steering: $400
New trackbar: $250
New Yukon hubs: $250
Shafts and joints: $800
Diff cover: $125
Total cost is closer to $5k when all is said and done. You can do it cheaper (skip the shafts, re-use hubs if they are good) but that probably only saves you $1k. You can save a bit more if you can do the gear install, weld on the truss, and make the trackbar and steering. Don't forget to include rear gears or install kit if you are choosing different gearing.