I found this collection from Johnny’s Selected Seeds. They supply a lot of wholesalers/ farmers, and sometimes backyard farmers have to wait.I personally wouldn't ever grow curly kale, other than maybe for baby leaves for salads. Really the only thing those varieties are good for fishmongers' counter displays. (IMO)
The heirloom Russian and Italian kales would be my first choices from that website.
Italian will be great as fairly big, mature leaves after it's been through a good hard frost- pick before the ribs get too fibrous and woody and you shouldn't need to trim them. It'll be nice just steamed until tender but not soggy; with a bit of butter, or lemon juice and olive oil. You can make a really good winter salad with blanched leaves too.
The russian can be eaten that way too but it'll be even better either as smaller, young leaves or once it's started to flower - small leaves and the flower sprouts they're growing next to should all be great.
Anyway, I see multiple Russian and Italian kales here:
https://www.johnnyseeds.com/search/?q=kale&start=0&sz=48&origStart=12
