Henri. For starters:- The levers with the pivot clamp and button ends to the lever are the "standard" Amal levers. They were fitted to Royal Enfield's (7/8") and Triumph (1"& 7/8") (Although the parts list for my l944 3HW quotes that type with the saddle clamp with two screws). They were also fitted to M20's G3L's and W/NG's later in the war as part of the drive for standardization.
Norton fitted Doherty levers in about 4 variations throughout the war.
Matchless fitted Solid combination Bowden levers to the G3 and the pressed steel Bowden combination version to the G3L.
I think the sidecar lamp you have is a generic thing that was produced by several firms. Later Big4's like mine were fitted with the Lucas variant which replaced the bullet shaped Lucas 1130 sidelamp. Ron