I have collected many kinds of these transfers over the years and have some from what seems to be the fourties or fifties. They are very fun to use. I usually just use a sharpened number 3 lead pencil (or mechanical) to copy the used up designs by using a window as a light box.. I don't want to distort the design by using the transfer pencils. The "lead" pencil lines are a skinner anyways and are easier to cover with your stitches. I have a few my mom used a tranfer pencil on and they are really too thick.
Some other patterns I love for embroidery are from say, bunny Hill or crabapple hill designs. They are very fun! Although some are so dang pricey!