There are a lot of makers marks and factory stampings. Main one is the crows foot /!\ the early ones are curly edge or what the RN calls the Pussers Arrow.
Canada CA,JI,LB.
Australia MA or OA, India is RFI, or GWR( Their railway works made a lot of weapons).
USA is either US Government Property, S for Savage or [S] for Savage Stevens, CP Chissapie Falls Factory .SA serial number on Thompson guns and Lee Enfield No4 MK1*.
Look for electro pencil numbers, this is a sign of Lend Lease equipment for the RED Army.Thompson guns especially late 1928A1 models with Lyman fixed sights AO serial numbers.
Inglis in Canada made for UK,Commonwealth and China. Look for JI and JII stampings. China used 7.92mm Mauser calibres and not .303. Canadian webbing is a lighter colour than British 37 patt. Zytel was the main manufacturer.
P14 and P17 rifles. P13 Bayonets made by Remington and Winchester but with NO oil hole in the pommel.
Also look for "local" stampings near the manufacturers original stampings.
Hope this is of help. Kind regards, Lester