Local guy here had a similar condition white 70 1500 when I was dailying mine in early 2000s, had around 35k on it, he used it regularly but kept it well cleaned and waxoyled He replaced the rear wing with a genuine one as there was the tiniest bit of rust starting on the bottom edge. A young girl was bought it as an 18th birthday present or the like, within a year or two rust starting to show at door bottoms, next thing was parked up with a cover over it. Often wondered what happened to it, just checked the reg, it's off the road and had an owner/log book change in 2015. Total sin, the wee car should have been preserved.
That red one is a peach, £10k might seem dear but an unrestored car is hard to find and have a coolness that can't be recreated!