I personally hope I am wrong. It is always fun and exciting to see rare, new and exotic hallmarks. Plus, if Trev is right than the piece could easily have traveled from Gibralter to Malaysia via a British soldier, sailor, merchant or bureaucrat as Malaysia was a British colony at the time as is and was Gibralter.
After your cleaning, the part that concerned me the most on the tip looks like its revealing its secrets. The green part and has turned brown with flecks of bright green which seems more and more like plate to me.
Plus the file marks on the tip are a good sign it is plate. There are at least 4 marks that are aggressively done. This usually means someone who only cared about its silver content, probably for scrap purposes, filed the piece for acid testing, discovered they couldn't melt it, and then discarded it somehow (unverifiable stories of old noble families anyone? ). In my company, we don't melt everything that comes through and try to sell anything of value. We also buy things from other scrap dealers outside and inside of New York. They send us bins of silver and often I'll find old pieces with unusual or foreign marks that amateurs from those companies have filed in exactly the same way. It might also explain that areas excessive plate loss from the acid testing.