parts for rebuild

OK, so not including engine and transmission, how difficult is it to find parts like kingpins, bushings, brake lines, steering components (like gear box and etc). I am pulling the body off the frame and just starting with that. will have 2 speed automatic rebuilt, but since engine cylinders have developed a "lip" at top of stroke, I may opt for bigger engine than original 6 cylinder (230 c.i.?). as you can see, i have many more questions than answers.
if i go with V8, engine housing will need to be modified, but will transmission, connections, etc. still be usable without MAJOR changes? is a change this big only for the truly mechanically adept? perhaps i should just live with a rebuilt 6-banger and be happy (i live at 6,000ft and mountain passes often go over 12,000, along with rarified air!). thanks in advance for any information.

haha -know rite where u are & done vail pass several times- personally - find a good 4 bolt 350 block - get a scat crank kit (850.00) for all, and a set of fulie heads -64cc- dump it in the van with a 200r or 700r4 trans &  climb those passes like everyones sittin still! Fulie heads here -redone are 350-400 -- blocks 100 bux & around 200 total=for machine work. Remember - U coulda had a ---V-8!!

Kind of hard to pull the body off the frame as it is one piece. Any V-8 will be better for power than a six.

ohhhhhh, I did not know that about frame/body being in one piece......I thought I had seen photos on this website of the body being off the frame.

how about my original question about parts availability.

and, twinpilot, ilove your response but only understand about half of it.......good thing for google, as I will be doing some homework!!

You are good for parts on some stuff (king pins etc.). The steering box itself may be a DIY or sent out re-build if it is an issue. The drag link and I think one of the tie rod ends may be tough to come by. You have a good resource on this site for parts and info on how-tos and stuff. Engine wise, a 250 would probably be your next step up and still be 6 banger, guys put in 292's but there are things peculiar to that swap.

very well. great info. as far as the frame/body being a single unit.......what did they do in case of body damage but intact frame? did they just throw the whole thing away?

Some of the guys on this site have pulled off some miraculous saves. If you get time go through the build threads in Members Show Case. What you can save is only limited by your resources and skill sets. Enough of these get parted out to come up with some pretty big chunks if needed. Fortunately you are a lot closer to good sources than us on the east side of the country. New replacement or patch panels are available from Mill Supply for most things behind the front wheel wells and up to the center line.
Just went back and looked up the pics. You have a pretty decent van to work with from what is shown! We love pics so feel free to over indulge.
On the V-8 swap, if kept simple not a ton of alterations. On a 1st gen, it will be throttle linkage and possibly fine tuning or up grading the cooling system. Have to open up the sides of the Dog House some to allow for the manifolds and maintenance. That's the simplified version. Having a removable or partially removable doghouse is a big advantage when you go V-8 also. I believe there is a thread or link to a V-8 swap on this site that is quite informative.