I am afraid that I do not know the manufacturer.
4mm Scale Whitemetal Bogies #17
a.b.s Models 4mm Scale Whitemetal Detailing Parts Please Choose From the List
Kenline 4mm Scale Whitemetal Fittings. Please choose from list
4mm Scale Whitemetal Bogie Sides #19 For Spares Only
4mm scale Whitemetal Left Hand Tool Boxes x 2 Unused #4
Pair of 4mm Scale Whitemetal Pipework Castings Unused No Idea What They Are