Thats about what I was going to guess @motownmama so I'll go with 1 carat or maybe slightly bigger. Looks like between
the two hearts you would get top of the finger coverage. They do overlap so that has to be taken into consideration.
So here are two hearts I pulled off of JA. A 1 carat and a 1.27 carat which looks way bigger. Maybe these will help you figure it out.