One possible source for Teletype roll paper is  POS Supply

Do a search on their site foe  B8716-225

12 rolls, 225 feet long with a 1 inch core

I bought a case 3 years ago for $95.95 -  with tax it cost me $101.71

I am only about halfway through it.

It is still the $95.95   It will be free shipping.

warning - It is on the  thin side (20 lb), but it works fine. It is also nice and white.

Tom    N3CRK