You can buy a flipper rebuild kit from Pinball Resource. I don’t think the kits come with the bushings but you can add them to your order. Do you have a manual/schematics? Pinball Resource has the license for Gottlieb so you can order an original/repro manual/schematic from him.
A great think about Steve is that his prices are fair and he charges exact postage. He manufactures pop bumper caps and drop targets in house. Other sellers buy from him and then dramatically mark up their prices.
You’ll have to call in your first order to set up an account. Make a list of part numbers that you want to order.