Finishing up the "N" box and including the only two I have in the "O" box with this post. New Orleans Silversmiths pictured first. I have only ever seen three of these in class, all acquired from Tom. New Orleans Silversmiths can be found as a company in New Orleans established in 1938 and still in business today. Inquiries to New Orleans Silversmiths regarding the ingots have gone unanswered to date but I will post any information I receive from them in an update.
The first of the following two examples was paired with a larger, similar cast example hallmarked by Noble Metals when I acquired it from Edward. I have these examples catalogued under Noble Metals but the casting is common enough that the afore mentioned pairing with a larger ingot alone is not conclusive evidence of its origin.
The only two from the "O" box pictured below. No information on Ozzie's; Oxford Mint, more modern and commonly represented by smaller pressed examples .