When did coke go from 5 to 10 cents?

I have several machines from the 50's and was curious just when did Coke change its price from 5 to 10 cents.  I have a one from Cav 51D from 1953 and a Vendo 23E from 1955 that both have ten cent mechs.  I also have a Cav 96 from 57 that I assume was ten cents as well.  I was curious because many restoration suppliers offer 5 and 10 cent stickers for the Cav 96 and 72.  But if the price change occurred in the early fifties, wouldnt these stickers be incorrect as well as a little silly?  Anybody know the exact year?  Thanks in advance.