When I rebuilt mine last year, I had to source everything as individual parts. I could not find a complete kit for the 71-72 model years. Rock Auto was my best friend, as well as Ebay. Just buy brand names like Moog and Raybestos, and you'll be fine.
I've gotten great prices on ebay on Moog parts. 4 new lower balljoints NOS under $200 (I have 2 cars to do), new Moog uppers $10 each, upper arm bushings $20 set of 4. Still need LCA bushings but they're fairly cheap. It just takes time to find what you need.
I got my rack and pinion from Autozone. If you search the site, you find my thread about it.
My 73 rack needs new inner tie rods & both boots. Advance has a rebuilt rack with warranty under $120 shipped using discount codes. I can't get inners & boots for that so it's a no brainer to buy a rebuilt. Only Autozone has the 71 rack for $136 if that's cheaper than rebuilding yours. I got outer Moog tie rod ends off ebay for my 71 for $15 a pair & I see them cheap all the time.
Neat trick a good friend taught me: You can save a few dollars removing the old bushings yourself. Just use an air chisel, they pop right out.
Installing upper arm bushings is easy too. A piece of angle iron cut to length to keep the sides from bending while allthread & washers is tightened to pull the bushings in. Lots of WD-40 on the allthread & bushings & you're done in 10 minutes. LCA bushing goes in with allthread, washers & a smaller chunk of angle iron to keep from bending the arm. I don't have a press so this saves money.