When it comes to parts, interiors, chrome and plastics are always difficult to replace. As a rule of thumb, the rarer the car is the harder it will be to get parts for. But there are exceptions because it's often much easier to make up parts for much older cars because they are less complicated and were designed to be kept on the road. It's that kind of design ethos that keeps many classic Land Rovers going - they were designed to be fixed anywhere with whatever you had to hand. The introduction of systems like fuel injection means that from the late-1970s, cars became harder to fix - and this is the era I think you're referring to. Don't be fooled into thinking that high volume production automatically equals a high survival rate - plenty of 1980s Fords have fallen by the wayside because getting the right parts became very difficult. Vauxhall also had a policy of binning spares for anything over ten years old (although some parts were bought up by specialists). Yes, there were more of them in scrapyards to plunder for parts but that's getting harder now. Ultimately, it's always easier to get parts for high-value cars - whether it be a 911 or a Mk2 Jaguar. German manufacturers have really targeted this lately with Mercedes, BMW, Porsche and Volkswagen all offering specific Classic schemes (as does Jaguar Land Rover) - but the price is high. Some cars are kept on the road because of strong club support (the UK arm of the Opel club used to do an annual trip to stock up). And domestic UK manufacturers are often strong for many reasons - clubs snapped up spares when factories closed, or people's families worked at the factory and they stockpiled parts. In the UK, you'll find enthusiasts with a shed full of Triumph spares, in France it could be a barn full of Peugeot parts. Swedish marques like Saab and Volvo also benefit from strong parts support. Prices for European spares can be heavily affected by currency fluctuations. Some clubs will get a part remanufactured if there is enough demand from members, which can make it difficult for smaller clubs with low-value cars. 3D printing has the potential to be huge - it's already being used to make up parts for historic racers and once the price lowers and the technology becomes more available, then it could help keep lots of cars on the road. Whatever car you're looking for, do your research and speak to the club about parts support.