As far as pricing I was just guessing on the labour. Still have not caught up with Matt, we were both out of town for the weekend, but if you delete the frame stretch and the cab swap, I cant imagine that it would be too difficult of a project and we have both done solid axle conversions before on Toyota trucks.
The cheaper end of the axle spectrum is going to be buying something used like this that is basically stock (mid 80s Dana 60 for $900)
http://www.pirate4x4.com/forum/showthread.php?t=966242&highlight=dana+60
or a Super 60 like this:
http://www.pirate4x4.com/forum/showthread.php?t=966047&highlight=dana+60
And this is what fully custom axles cost:
http://www.pirate4x4.com/forum/showthread.php?t=959896&highlight=dana+60
Leaf springs are relatively inexpensive, even nice springs like Deaver arent too much. You might even find something like this (D60 front with springs attached)
http://www.pirate4x4.com/forum/showthread.php?t=752030&highlight=deaver
if you dont mind used parts, bargain hunting and being budget minded with money and time, you can find good deals. The down side is that it will take longer to complete the project due to shopping time.
An NP205 is a very beefy stock transfer case. Several versions available along with plenty of stock and aftermarket parts. Something like this would keep you from trying to adapt to the 2WD transmission:
http://www.pirate4x4.com/forum/showthread.php?t=961567&highlight=np205
this would be the higher end of a transfer case, around 2 grand used and can be 2500-3000 (or more) new: (there are two speed and four speed versions, divorced and married, different gear ratios, etc., all those affect price)
http://www.pirate4x4.com/forum/showthread.php?t=949264&highlight=atlas
that should give you some ideas. I posted links from Pirate because its a huge offroad board with lots of members so there are lots of parts, threads and posts. I am not advocating that you purchase any of those items.
EDIT: OvEx for this year is the same place it was last year, south of Tucson, AZ, cant remember town, but Armando or something like that comes to mind. Just google it...