cost of narrow/custom axle 12 bolt?

found a 12 bolt locally for under $500 with 3:73 and posi but its off a 70's truck so obviously would need narrowed and new custom axles built. never had anything done like this. but know a couple guys that could narrow it reasonably is it still worth doing?

If you do buy it,you might try dutchmans axles in oregon,i did a ford 9 inch and they made the axles for $130.00 apiece.

Just a heads up that truck 12 bolts are weaker than passenger car 12 bolts.
You might want to look into it before buying.

ya 12 bolt truck is different then 12 bolt bolt car. I've heard the car 12 bolt is the more durable of the two. BUT with that said truck diffs have been used in cars before:)