Tea Plant for New Hampshire

Yes, I'm looking for black tea, Camellia sinensis, I believe. I've e-mailed a few places, and they think that this area may be a little cold. I figured if anyone has a hardier version, it would be someone in Canada...
What about planting them as a shrubbery line in front of the house? If I covered them with straw and put a wooden box over them, do you think they'd live through the winter? From what I saw on the internet, it seems that tea farms prune them to 2-3 ft. tall, and it looks like they have some beautiful flowers for a couple of months in the spring. Looks like it would look great and I've have all the tea I could drink... Is this reasonable, or am I way off base?
An alternative might be a couple of potted plants that I bring in for the winter. Would it store OK in a 40-50 degree F basement for 4-5 months? How big a pot would that be?

Tea (Camellia sinensis) would not be hardy in your area, and I don't believe that providing the winter protection you describe will be enough to help it get through the winter.
Bringing them indoors is always a possibility, but I cannot say if storing them in a cool basement would work. That works with some plants such as geraniums that naturally endure a cool, dry period in their native habitat (South Africa in the case of geraniums) but it is not an assured thing for a year round evergreen plant such as tea. It may be worth trying with one or two plants, but I would hesitate to try it for all of the plants you want to grow.
As for the prospect of harvesting your own tea for drinking, this is certainly the point of growing herbs for yourself. But in the case of tea, you may find that the yields you get from plants that spend all of part of their year in pots may be too small to make the whole exercise truly satisfying. I think you will find that it will take several years before you get large enough plants that yield enough for the occasional pot of tea.
I should also point out that black tea is a fermented product which requires an additional step after harvesting. Green tea, on the other hand, is the raw leaves in dried form, which is much more straightforward to produce from your own plants.