I found another, with a body shape like yours - it is properly called a Pistol Flask.
http://www.finesportingcollectablesltd.co.uk/pflask.htm
The asking price of their unmarked flask is about $500US
Yours is made by a known, quality maker, ergo, worth more $$$.
Item Code PF0110, Price £275 (GBP)
"A small pistol size three way powder flask with a top compartment for balls and a screw off base compartment for percussion caps. Measures 3 7/8" overall. Untouched condition with good patina and traces of the original lacquer. Would be suitable with a pair of percussion pistols. There is a small dent on one side and the spring is broken."
I seriously doubt that anything of this quality can be found on Sleaze-Bay, who can kiss my red, round, rosy, rotend, rotating rectum.
Someone with a cased set of dueling pistols, missing their flask, would buy it in a New York Minute.
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