It is 11x17. I don't know a lot about the paper they use but seems Marvel might provide it. There is a super light colored Marvel Comics logo in the top left.

I actually forgot... I have a couple other indy pages I got before this... I don't even remember the book they were from. They were done on 11x14 pages. I got them when I was really young and didn't take very good care of them sadly.

Look forward to seeing yours!