Olds rockers

I have a set of adj. rockers for a 371 that I need to identify as to manufacturer. Wondering if the vetern Olds fellas on here can determine what they are? I am in need of one replacement as one is damaged.
Pics attached for reference. They all have a stamping number on the bottom that varies from one to the other. No other markings anywhere else.

 

If you can wait until tomarrow, ill go check in my shed. There is a bucket full of them, Gotha,thats what you have, i also have McGurk, Isky, M/t, Thomas. Also in 1.5 and 1.8. You have 1.8 ratio. Should have you covered Call Me 319-234-8679 Thanks R&P BLOWER SERV.

 

check with harleycontractor here on hamb he had a set and a few extras in a can

 

Here is a pic of 1.8 Gotha rocker arms.
So that should rule them out!