Anyone been into any little local shops lately that had individual teacups for sale?
Not hunting a set, just a single teacup, maybe two. The type that would inspire
a grown lass to utter phrases like 'how adorable' or 'Oh, how pretty.'

Bonus points for being predominantly white with pinkish blossoms.

Try the antique stores along Western near VZD's.

The first thing that popped into my head was the Rink Gallery in Bethany. This place is VERY hit or miss, but there is tons and tons of stuff to sift through. rinkgallery.com

I would suggest Inspirations Tea Room in Edmond. It is not just a place for ladies (and the occasional gentleman) to lunch, but they also have a nice retail section where they sell all kinds of teas and tea accessories, like tea cups as well as a variety of olive oils, and decorative items.