I would bet a full third to half of people here have a plasma cutter in their garage. Perfectly useful for making the occasional large washer. At least a dozen or more members here have full CNC setups.
A simple circle cutting jig and a plasma torch or even an oxyfuel torch could make OP’s washers.
CNC Laser and plasma are more accessible than ever.
Ever heard of SendCutSend? They’ll make you all the washers you want in whatever size you want out of any metal.
Just because you don’t have a 5’X10’ fiber laser in your home garage doesn’t mean there aren’t thousands of guys with a torchmate or something similar.
Hobby grade CNC has been around for YEARS and will only get cheaper.
"Here" is not relevant to the rest of the general population in the USA (at least).
Nor is "here" an accurate sample of the amount of money people have to sink into a shop or shop equipment.
Yes, I have heard of "Send Cut Send". For simple parts like washers that can be ordered from their site, fantastic.
For other parts, things that need to be drawn in CAD, that can be an obstacle.
The washers can get expensive if you only need a couple (minimum charge, shipping).
There is a huge difference between someone that is mechanically inclined and someone that isn't.
Yes, there is the internet and YouTube. But, when you don't know what it's called, searching can be difficult.
I'm glad that I can do what I can do, but that doesn't mean that anyone else should be able to do it too. There's also many, many people that know more.