even though it is not Austria but the neigbouring country Hungary where I am from, but there is a decent little family-run webshop postcardsisters.com
I got my Xmas present of 50 cards in a bundle for a relatively friendly price postage included. They also give you 15 % of discount when ordering for the first time.
Check it, you might like it.
Another option that I have just found is in Russia. They offer a huge variety of cool cards, even cheaper https://postcardpress.ru/en/
I am planning to order some cards from there.
Hope you will find some great card here or somewhere else,
Thank you so much for your reply! I’m sorry for reacting so late to it. I didn’t get a notification and didn’t see your reply.
These seem like good alternatives to try out! I will look into them. Not just for my partner but for myself as well