Apparently, the bolt for a .22 rimfire 73 is an item that is very difficult to find. When a part cannot be found, the only choice is to make one, which is what, through photos, I will describe in this post. The original bolt and extractor were "modified" beyond salvage but, luckily, the customer had another rifle that could supply a bolt to use as a model.
The bolt itself was machined from a bar of 1018, while the extractor was made from 1095 and heat treated as any other spring.
The new bolt installed.