Hi and welcome to YT. I'm sorry you have had to face such an illness, and especially at such a young age.
I found the link below for a New England yorkie rescue. Even if they are not willing to give you a yorkie, maybe you could possibly foster one for them. Or perhaps, they have one in a price range you could afford.... or.... maybe they would work with you on the cost.
Good luck on your search, and I hope you find that special yorkie for you to love!
Yorkies Inc.