War Baby! by Ruth says if the "N" mark is on the right lug and the lot number is on the left lug, it's earlier than mid 1943. If the "N" mark and lot number are both on the left lug, it's later than mid 1943. The lot numbers range from 8 through 14. Based on the barrel date, I would expect a correct bolt for your carbine would be one with both marks on the left lug in the upper range of lot numbers.
If I remember correctly, I gave all my Carbine books which included War Baby to Karl Reutling when I sold him my carbine collection back in '99. I should be getting a new copy in a week or two. Then I need a bolt disassebly tool because I gave all my tools to Karl too, lol. After that I can begin the process of restoring my carbine.
Masquerading as a man with a reason My charade is the event of the season And if I claim to be a wise man It surely means that I dont know
I have discussions about my carbine going in 4 different threads. They all started with different questions but they have evolved into very similar threads so I figure they should be combined. Here is the link to that thread to the thread with 12 pictures.