Attend a petro swap meet and keep a sharp eye out for vendors with patches. The Oct. 29 Chicagoland show in Peotone, Illinois would be the closest one to you. The last several years at the spring swap meet at Peotone there were vendors with lots of patches. This is the first year for a fall event there.
See the Oldgas.com
Events page for more event info.
Another option is to talk to a company that does custom embroidery like putting logos on shirts and hats. I'm sure that they could custom make one that would look like the old style. You would probably need to show them an example of the style you want. This will cost more than a vintage one, if you can find it.
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