I bought my Sintra here:
http://www.matgraph.com/products_main_temp.html
They sell it in 4 X 8 foot sheets for signs, and ship by truck freight. It was too pricey THAT way, so I found a nice alternative.
They also sell CUT pieces here:
http://www.matgraph.com/servlet/SelectCircle
Select "Rectangle" (it defaults to "Circle"), type in your desired width x length dimensions, then select your material from the pull down menu.
They have Sintra in 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 10mm, 13mm, & 19mm thicknesses, in varying colors. I bought several sheets of light gray 3mm Sintra for my armor, then 2mm white Sintra for some of my "accessories".
For reference, a 12" X 12" sheet of 3mm light gray Sintra is around $1.17. I found out on checkout that if you want a sheet over 30" X 30", your shipping is astronomical, so try to stay at 30" X 30" or LESS for each sheet. Also, they charge $30.00 per ORDER to cut Sintra to size.
It seems like a lot, but the Sintra is REALLY inexpensive, and so is the shipping. They're in Chicago, and I got my order in 3 days. I ended up with eight 12" X 12" sheets of light gray 3mm Sintra, one 30" X 30" sheet of white 2mm Sintra, one 18" X 18" sheet of light gray 3mm Sintra, and one 24" X 24" sheet of light gray 3mm Sintra, plus shipping AND the $30.00 cutting fee for about $50.00. I'll have enough left over to use for other costumes.
By the way, they also sell ALUMINUM, STEEL, and Plexiglas.
Hope this helps!
