I have resisted new paint, interior and even an engine rebuild. My Sympathetic Resto consists of cleaning, polishing, greasing, a few new seals and powder coating of rusty tinwear. I agree that costs can start to get out of control but in alot of instances the original parts cleaned and repainted are much better than new! I managed to find NOS running boards from www.vw-classicparts.de they are part of the VW factory and are located in Wolfsburg, they were 59 euro each.
I also got SC type keys cut there from the lock code number, I think they were 13 euros each also they do the rare KOLB blanks for 5 euros.In total I think I spent £35 on replating all nuts, bolts and brake pipes. The moral is is doesn't have to be that expensive if you are careful.