This Remington was made in 1973 if the date code is XX9 or '72 if XX8, not so clear to read from the mark, in the rough '70 production or replicas was at the top for quantity of small factory, but in many case at the bottom for quality
Without a clear factory mark i think is impossible to understand who made it!
One way is compare the revolver with other with well knowed producer, like mr Pietta said me during a telephone call where i asked him spare part for an old remington, the difference from makers depends for first from what original they examine for cloning, and than fron the tooling capability of the workers and the goodness of tool machine!
By the way, many small parts, like spring, were made not at home but from small workshop in the area and could be a high compatibility even in different production factory (or best to say, small family workshop where they finish rough cast, barrel and other part buyed outside and only fitted toghether).
About numbers, besides the serial numbers, often, there is an assembly number, hand fitted part need to be knowed during the building process
Rusty