Help in identifying key blank for small Eagle PTPK padlocks

[candado3]

I’m here again asking for help in identifying the key blanks needed for some small Eagle PTPK padlocks that I have plus some other information. I have two locks without keys and one with a key and also found a photo of a similar key on ebay. The key that I have inserts in all three of the locks that I have even though the keyways are a different size.

Smaller lock the plug is ~9mm diam and keyway ~5.62mm

Larger lock the plug is ~10mm diam and keyway ~7.3mm

Also can anyone elaborate on what the rectangular piece of brass insert above the plug on the larger lock is and how it works in the lock?

Thanks in advance

I have attached photos,
One is of the Larger Eagle lock keyway that I changed to B&W which shows better