Technical Help in identifying early Hemi valve covers

I recently purchased these on Ebay. I want to know if anyone can help me identify the manufacturer and possible year produced. They are cast aluminum and have no markings on them. Any info helps.

 

Maybe Hot Heads? http://www.jalopyjournal.com/forum/...y-post-pics-here.112948/page-15#post-11627137

 

Check post #120.

 

I contacted HotHeads first thing. They said they had never seen them before. Obrien truckers also look different. They have no markings anywhere, but are stamped for breathers on the inside. A google image search found nothing even close. They were found at an estate sale in Pennsylvania.

 

not the ones in that ad, the location of the plug holes compared to the fins is different.

 

I saw those, but I think mine are a slightly different shape. The top is squared off. The spark plug holes have two O ring slots.

 

Good point squirrel, their are seven fins total