I've been online and ordered piston rings, big end shells, cam followers, gaskets and seals.
I still need sludge trap plugs and oil check valve spring and ball and clutch centre tab washer.
Today, after emptying and filling the dishwasher and reassembling brother-in-laws mower motor I have been mostly scraping old gasket off and decoking the combustion chambers. I will strip, decoke and regrind the valves when I get my new spring compressor. When I have all the new parts I will be carefully washing parts in something suitable, blow drying and wrapping in plastic bags ready for a surgically clean rebuild.