I heard an industry rumor to the effect that David Austen has stopped selling their roses through other brokers (J&P, Weeks, Star, etc.) and now require retail nurseries and garden centers to purchase directly through them but I don't have any confirmation on that. The broker wholesale catalogs (at least some) still have Austens listed so perhaps this is one of those rumors that has gotten started without any foundation :-)

FWIW, fewer and fewer retail nurseries are offering bare root roses or much of any bare root stock these days. The roses come in in early spring already potted or are immediately potted up once received. While it is more work initially, a potted plant just requires much less attention and care than one that has roots exposed. You'll still find bare root stock available but selection and quantity are declining, even with common bare root stock like fruit trees and berries. Mail order sources will be different.