Just tore down my "new" Long Branch MK1*.
Year: 1943
SN: 41L2850
Barrel: 2 Groove
Rear sight: CMK 3
All LB + C broad arrow marked + DCP (nothing foreign)
Except for a vertical line, matching on both sides above mag release, I don't think there's a non-production ding.
Mag + Furniture: LB marked
Unusual mark on handguard:
Attachment 121950
See it here: https://www.milsurps.com/showthread....181#post510181