I can see the right column are numerals 67, but the rest does not make sense and a bit suspect. Can you blow up the photo of the marking a bit more, to try to make out what that larger looking character fourth from the left is.
Hey thats when I got tangled up, I thought it was gatsu but that didnt make any sense,i thought the 3rd from the left was shou ,and top-month certainly didnt make any sense.is the " --l " symbol one symbol or two as in "--" ichi (one)and " l " ..the first one on the left is too blurry .Well it kept me occupied all night thinking about it, now I can go home and sleep ...Dave
I suggest you to check with someone who knows Korean.
"口-l" & " 畀" There are similar Korean characters. Please see attached photo.
"上" This can be Chinese “up” or “upper”. It is used in Korean & Japanese too.
"六七" = Chinese “6” & “7”. They are used in Korean & Japanese too.
Not suprising theres a similarity, kanji is a chinese rooted system, . the problem doesnt seem to be that the symbols cant be read, they just dont appear to be lodgical when read...However maybe they would in korean or chinese, I dont have a clue or claim to..