I think you did very well on your buy. It couldn't be built for that kind of money. A few minor items that you mentioned are easily corrected. Like you said going with 500's. Excellent choice in my opinion. The rust free part is the best part of your purchase! Nicely optioned (4V-Ram Air, 4 speed, 9 inch), same owner 35 years, appearance shows it was extremely well maintained and a rebuilt engine to boot. The list of positives are impressive ones.
Any future plans for a repaint? As in original color?