I feel for you. Because of border restrictions, many nurseries and seed houses here in the US have quit shipping to CA.
St Lawrence Nursery is close to the CA border (in Potsdam, NY, +/- 30km from Ottawa), and grows all of his stock in zone 3-4, yet he has chosen to quit trying to play the US/CA border game. By doing so, he has eliminated the majority of his customers who actually need that hardy
root stock.
I can understand
authorities trying to protect existing crops, but when is
enough, enough?
Bottom line: Do you live in an agricultural area? If so, go to the
local feed/seed dealer and ask him "Can you order it for me?" Perhaps he has had customers request species before, but not a full 50# bag full. He doesn't want to buy a 50# bag,
sell 10#, and have 40# turn to mould before he throws it away. If he knows that you want a quantity, you can probably buy it cheaper through him than through the internet - he is dealing with local wholesalers, and his shipping is a fraction of what you would pay to have somebody ship it from South Carolina.