Re: Who made this??
Well my guess on what characters stamped mean are...
C=Chrome Moly
5=#of lands
7=caliber or maybe even contour but would think caliber
However, that is just a wild assed guess. Numerous makers stamp everything but their birthday on some. Obermeyer, Krieger, Bartlein, Rock, Shilen,Douglas and Border are to name a few. Some I have seen with little info would be Gary Schneider who marks them similar to yours. Also Hart is skimpy on specs they stamp. If Hart said it wasn't theirs I would believe them. Found a blank on GB awhile back I was sure was an older Hart but seller listed it as a Shilen. Sent a pic the seller posted to Karen and she went out of her way to find an older employee that confirmed it was indeed a Hart.
If it isn't a Schneider then it could be some lesser known such as Half Moon, Schultz(no longer in business) or a Lawerence etc. or????? Never had a Lilja, so don't know how they mark theirs. How old is it? Is it chrome moly or perhaps stainless?
Next one with any experience who sees your pic may know instantly whos it is or you may never find out if the seller don't know!
Send a pic to Gary Schneider, may well be your best shot and it is his.
Sorry for more confusion.
Respectfully,
Dennis