I don't know if this will answer the question or not but as far as blanks and codes go, I just take my key to any hardware store they duplicate it so it is a common blank (newer 1951-55 and older 1947 - 50 cars). The store has always had blank for the early cars and the late ones - I've had both made. If you are looking for a blank with a "K" stamped in it, then yes, that's a Kaiser product and you'd have to find a vendor for it but I often see "Rare Kaiser key blanks..." offered on ebay when they are nothing more than the common blank you can get at any hardware store.
Does this help?