Well, I just saw another factory letter on the RJF prefix Melonite 4566. It was with an example for sale on the big auction board.
The letter states that these guns were produced in 2009 with a production code of 148670. The production run was for 119 units. The unit in question shipped from the factory in May of 2009.
So I guess this will be the number...…..until another letter with different info pops up.
Regards 18DAI