i used the left lever for my good fixie, and used the right one uk style on my townie. i bought the tektros simply because i don't ever use my brakes, and couldn't justify spending more for the canes. when compared side by side, they look the same. and when i need them for ebraking, i am sure they will work just fine.
but yeah, they should sell them individually. most people aren't building up multiple bikes like i was at the time...