Chinesium in two takes

Find a local rebuild shop and start taking every one of your alternators and starters to them. Keep them in business. You will get a much better product. And the cores don’t get thrown around all the way back to the China (CCP) Rebuilders.
Where do you find rebuilders anymore? You purchase an alternator or starter and get charged a core charge, so someone is rebuilding. Ask the parts store about an alternator kit. Not available is the story. Used to be able to get them anywhere, and the rebuilders have them. Used to be able to get wiper refills with just the rubber and the stainless supports, slide them in. Cost $5 for a pair. Now you have to buy the blade. Cheap in $CDN is 15, each. Then you get into the fancy crap that does not last and costs $40 each.
Nor hard to figure out, profit margins. A reman alternator cost me $275CDN for my '99 Chev. A rebuild kit would probably be $50. At 20% markup, their bank account balance looks a lot better with the reman. Mine looks like **** though!