M47 is the designation for made by Birmingham Small Arms (BSA)
FY is a Fazakerley designation
My error before: It's not RMP, its FMP -- Federation of Malaysian Police
The gun's receiver (from your first pictures) is a Faz, but it's constructed with both Faz and BSA components. This isn't unusual, and, as Capt. Laidlerhas said so often, when guns received repairs, the Armourers grabbed whatever parts were necessary to make the fix -- giving no regard for the part's origin. And many were built at the factory from mixed origin parts.
In M-1 parlance, this gun is referred to as a "mixmaster," which is not a degrading term, it just refers to the multitudes of repairs made to an old girl who's seen a lot of action in the field.
Please, don't worry about restoring this to a "pure" gun -- she's a mongrel now, always was, and should remain so. Let the gun's varied parts speak volumes to her colourful history. And don't worry about "dumb" questions -- I asked the same types of questions once, and fortunately a lot of patient members answered. But do go back through the multitude of threads (see bottom of this page to start) and see what many many others have learned. And be sure to read every one of Captain Laidler's expert advisory posts.