What do you want to spend? I have a 70 r/t with seats, dash, console, door panels, a lot of its there, just needs to be restored, but I am going to restore that car when I am done with the bee... I could possibly be drifted to sell it for the right price...
BUT the best way to buy it is probably piece by piece, what is your original interior code on the fender tag? color and style?
So you need the entire dash, frame, cluster, pad, bezels, lower trim, radio, glove box, wiring harness, heater control, ash tray, map light, etc?
I have lists from when I put everything together from my cars..
pillar covers, kick panels, coat hangers, door panel lowers, door panel uppers, rear door panels, 8pc arm rests bases and pads, int door handles, window cranks, window crank base washers, door lock pins, door lock bezels, carpet, dome light,
Headliner, headliner teeth , headliner pad, front windshield headliner trim, side door headliner trim, headliner bows, 5 pc rear window trim, package tray, pt jute,
headliner cups for the bows, headliner clips, door panel clips, headliner rear wires, screw kits, seat frames, seat rails, aluminum seat side covers, seat covers, seat foams, seat install kits,
I know my bee's dash (which was complete needing resto) cost me thousands to restore, just all the little clips and screws kits were a couple hundred for the interior, then wiring another $600 or so, dash, dome light, console, after buying all the relays, seat covers, and door panels for the 70 charger gets expensive because of them upper pads(a friend of mine just bought a set of front and back for $900 lol), could cost another $1400 depending on what you have, seats needing resto probably $600 or so...
I hate to say this but you may be better off buying a car you find with a complete gut, and selling what you dont need, I put a couple interiors together for 68-70 b-bodies and I am going to guess, you are looking at $10K+ for show and $5K+ for driver...
A better option may be to go custom, I have done custom hot rod ford interiors for much much less than any mopar gut has cost me... Get some card/wood stock and make the door panels with some padding, piping, and vinyl, get some donor seats, a carpet for $90, and headliner for $70, a dash frame, some new gauges fit in with carbon fiber or aluminum plate, a painless wiring kit, a package tray, and you can make almost everything out of vinyl covered card/wood stock, kick panels, dash pad, pillars, visors, etc...
It adds up so fast, I am into my seat belts for over $600 after buying the bolts, belts, covers, etc... I think the interior on my 70 bee is past $10K right now, and I had 90% of it!!!, lol... IMO, start looking and doing the math, see what makes sense for you, finding someone with a gut all together that wants to sell it, is tough.. I have 90% of that chargers gut, rallye dash, cluster with tic toc tac, buckets, rear seat, console, door panels and tops, arm rests, most seat belt stuff, kick panels, pillars, visors, etc. and it would all need restoration of course, its 45+ years old... It is high black bucket console interior, fender tag says c16 h6x9....
I have a lot of it wrapped in plastic...