I get sleeves at Grizzly.    https://www.grizzly.com/products/grizzly-1-1-2-dia.-x-5-1-2-hard-sanding-sleeve-a80-3-pk./h6670

Look around, they have several sizes, but they are not organized very well.

They also have longer sleeves that could be cut down.

I'm probly going to let you down but, I swear I won't keep you down. John Hiatt