As someone suggested you might be better off getting a donor rig and swapping the drive train over.
You can usualy pick up a rig that has no engine or tranny for around $500.
Then sell the front and rear axles and you will break even on the whole deal.
I have a sickness that makes me buy old rigs in fields and then try to restore them.
In the end I just scrap them out.
By the time you buy new fenders and bed sides, a hood, rockers .... the list can go on and on.
And get realy exspensive fast.
My K5 is realy rusted out and basicly needs a whole new body.
That is if I want to restore it.
But I was lookin at it and decided that the best route to go is a 4" lift and just cut out the rot around the wheel wells and stuff 37" tires under it.
But I would say that isn't an option for you.
LMC has a good selection of replacement panels and such.
And they are reasonably priced.
Go to http://www.lmctruck.com/
and they will send you free catalogs.
It sounds like ya have a good rig to start a project with.
Have fun and good luck.