I have 3 Vantage watches with mechanical movements. From what I have found on the interwebs Vantage was a budget brand for Hamilton. All the Vantages I own and from the ones I have seen on ebay have movements mark Standard Time or Standard Time Corp. The ones I own don't have the country from where it was made on the dial or the movement. From what I have read Hamilton had a partnership with Ricoh watch company of Japan,which only lasted from 1962 to 1964, to produce the Hamilton electric movements. I have seen one vantage with a movement marked japan
also have seen a vanatage electric with and ESA 9154 that was marked Standard Time and swiss
The 3 Vantage watches I have are marked standard time are very similar to my Enicar movement, a Laco, and a Endura I saw on ebay.
pic of the 3 vantages
here is my vantage marked Standard 90, size is 11.5'''
my other vantage marked Standard Time caliber st 91, size 10.5'''
and my last vantage Standard Time caliber st 92, size 10.5'''
my Enicar size 10.5'''
and Endura marked canava and Candada, here is ebay link 1940-50's Endura 17 Jewel movement Made in CANADA - eBay (item 150539162873 end time Jan-01-11 14:21:59 PST)
here are the links were I got info from
???? ???????? - ????? ??
Hamilton Ricoh Watch Company