help finding a 5' aluminum

hey guys im looking for a piece that is a 5inch wide aluminum dome shape like my picture below, and around 1-1/2’ and about 3 to 4 inches high so my flashlight body can screw into it.

if i cant find anything close ill have to have one made and it will not be cheap lol

something like this on ebay item# 160778205553

piece i need is in DARK GREEN/GREY the black is my 5 inch aluminum pipe

maybe you could find a 5” reflector?

someone gave me a idea of a 5’ headlight, but in not sure if it will be thick enough to have it threaded, and to screw in to my body