I actually bought a box of Cox Orange online from this orchard in VT. They were good, but the descriptions are always better.

https://www.scottfarmvermont.com/coxs-orange-pippin

Salt Spring Island, BC also seems to have a big heirloom apple thing going on, for any Van folks. (ex: I bought a couple of trees from this orchard https://www.saltspringapplecompany.com/)