There are several zone 6 Camellias that can handle colder temparatures. Be sure to use a well drained soil medium when planting any Camellia as they prefer fall planting with less watering than you might think. In NC our soil is clay so we prefer to use pine bark soil conditioner when planting Camellia, Rhododendron, Mountain Laurel, and Azalea.
Ashton's Cameo Camellia
Camellia japonica 'Ashton's Cameo'
Just so we're clear, this name does not refer to Ashton Kutcher's cameo in 'Bad Moms'. Rather, the 'Ashton's Cameo' camellia was developed in Ashton, Maryland by Dr. William Ackerman in the 1990's. Cold hardy to zone 6b, this camellia has moderate, spreading growth and heavy bud set. Blooms October to November and has an anemone form.