Aarhus University Press from time to time releases their books for free in pdf format for limited periods.
Medieval Garments Reconstructed by Lilli Fransen, Anna Nørgård and Else Østergård is currently available. It's the book that contains the study of all the Greenland finds including the famed Herjolfsnes G63 gown. It also has scale patterns for each of the garments. If you're looking for the G63 specifically it's on page 100 of the pdf listed as "Museum No. D10594."
Download it now for free! Even if you don't think you need it, it's worth it. This book runs just over $40 in hardcover off Amazon, so 3 years from now when you decide you want to try and sew an appropriate medieval gown, you'll have this pdf sitting on your hard drive.
I will be sewing a G-63 with modified large angel-wing sleeves for the gown to go over my doublet.
It also contains several hood, hat and hosen patterns for your consumption.
http://en.unipress.dk/m%C3%A5nedens-gratis-e-bog/
