This type of certificate was something that local printers would buy "blanks" of and then print your name and other details. Yours, being blank, was probably from a book of them the company owner had to issue as needed. Here is basically the same design for another oil company, but dry cleaners, used auto dealers, or anyone who created a company could create stock from these types of certificates.
Printed by "GOES" a famous lithography firm
not mine, from internet

GOES is still in business printing the contemporary equivalents
