What chassis is that Chevy, 3/4-ton? The front axle is meh then, it's the same 10-bolt used in halftons but with 8-lug outers. If that was a 1-ton D60 tho, i'd try to make it work.
Transfer case is easy enough, use a divorced-mount NP 205 out of either GM or Dodge truck, both will be passenger-side drop axles and t-cases. And you can keep your existing transmission, instead of looking for a 4x4-specific one. But you will have to do exhaust work to clear the t-case and the front shaft.
Then again, if you want cheap and bolt-on, there is always the D50 Ford put in the F250s. Actually the true bolt-on will be the D44 HD, after some work at on the front of the frame horns to fit the leaf spring shackles. But the D50 is much stronger.
And you don't really need to replace your rear axle. Just get a front axle which has the same gear ration as the rear you have now. Unless you decide to do the '05+ Superduty axles swap, then you'll need both front and rear. Won't be cheap, but it's easy and the ride is great. Not so much with any leaf-sprung front axle.