Model a key?

[e70]

I read an article by cal Allen regarding that this key is a mid '28 key (short run -2 months) I have never come across one until finding the two attached far left in picture below. Neither key is A stamped. One side is spelled out b&s while the other side has the b inside a diamond. Has anyone ever seen this key A stamped?? Thoughts??

 

[burner31]

I have an original key and pop out in one of my boxes, I'll dig it out and post a pic

 

[Mark W.]

http://www.fordbarn.com/forum/showthread.php?t=145636

Looks like these - long gone now, but all were "A" marked.

 

[burner31]

Looks like my key is NOT original, but here's the pics anyway.
Has "Briggs & Stratton" on it, number #A1089

The other key I have no idea whats it for, number on it is #347