"... at least eight feet tall? "
That would be just about any of them. LOL!
Camellias come in different flower forms and shades of white, pink, red, variegated. So you might look them up and see what you prefer. For zone 7a, you'll want a hardier variety.
Consider the April series, since they are easy to remember..... 'April Dawn, April Tryst, April Kiss, April Remembered, April Rose, April Snow, etc.'
Any of the Ackerman 'Spring' or 'Winter' series such as 'Spring's Promise', 'Spring Cardinal' or 'Winter's Fire'.
Any Longwood Gardens introductions such as 'Longwood Valentine.'
Any super hardy camellias from Korean regions such as 'Korean Fire', Korean Snow.
A good list of tried-and-true japonicas for zone 7a should then include (besides the April series): 'Lady Clare', RL Wheeler, Paulette Goddard, Adolphe Audusson, Gov. Mouton, Jerry Hill, Blood of China, Red Aurora, Prof. Charles Sargent, Lady Vansittart, Mathotiana, Korean Fire, Red Jade, Pink Icicle (Spring), Winter's Fire, Red Fellow, Springs Promise, Betty Sette, Korean Snow, Aida, Longwood Valentine, Longwood Centennial, Hokkaido Red, Spring Cardinal, Kumasaka, Berenice Boddy, Anacostia, Variety Z, Arctic Rose, Bloomfield, etc.
Species C. chekiangoleosa is especially beautiful and hardy.
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