people dont deal with spare parts unless the device in question is really valuable.

so you can deal with car parts or iphone parts or washng machine parts or laptop parts.

otherwise, like for example with the 1989 original game boy and later game boy versions, people sell broken ones cheaply on ebay. one time i purchased 5 broken ones and turned them into 3 perfectly working ones. But thats because there is a community behind this vintage computer game stuff.

apart from that, for anything else, anything where the whole thing costs less than 100 dollars, you can MAYBE get spare parts from the manufacturer, but only in a few occasions and when customer support is excellent.

its just not worth it. the few people that are really into it buy, for example, 50 broken flatscreen monitors all from the same company or even better the same model and turn them into 20 or 30 working ones. There is just no incentive to do it with lightbulbs or toasters or alarm clocks or small stuff like that.