Also, I don't make an actual envelope with flaps, I print out a scan of the front and the back at about actual size. I clean up the photos as much as possible, if the size is different I 'erase' the size and replace it with the correct size. I print front and back each on one sheet of 8.5" by 11" and then fold those over the patterns, put them in the clear sleeve and seal it and at a glance it's hard to tell it from the real thing! Even if I never sell them it alleviates the angst it causes me to have a fabulous pattern with no envelope!
I state very clearly in the listing that the envelope is a reproduction and not the original. So far, I think I've only sold two and have listed about five. Money wise it's not really worth all the trouble for most of the patterns I'm dealing with, which still sell at a lower price because they don't have the original envelope, and there's the cost of the printout and the time it takes to make it. This pattern, for instance:
http://www.etsy.com/listing/68544285/uncut-vintage-1969-mccalls-flared-dress, won't net me very much but I just felt compelled to do it! Finicky Finds was very kind about letting me use her scan.
