As far as I know, Freestyle is the only dealer that carries this paper. Is it manufactured in this size? I'd give Freestyle a call about that, and with any luck, they'll chime in here, as they are an APUG partner.
Freestyle is also a FANATIC dealer. They give top notch customer service and I feel they really deserve my business. They are not the only dealer I buy from but I feel their support support of the analogue community is unparalleled.