Lemme add my support to everyone that says buy an OLD drawknife. In order to get a good modern draw knife, you are going to pay a heck of a lot of money. I spent years cussing, swearing, and resharpening a cheap piece of modern crap draw knife that had to have been made of some form of iron that was semi-liquid...even debarking a green piece of pine would roll the edge or dull it to butter knife sharpness.
Every second hand store, junk shop, flea market, and garage sale that had a draw knife wanted $25 or more and the blades were always ground down until there was nothing left. Never did score a good find. So I bit the bullet and purchased a good one from Lee Valley Tools. It is the drop forged Austrian model that is Rockwell hardness of 58-60. It came sharp enough to shave a newborn frog's buttocks and all I have done for 8 years is lightly hone with a very fine grit diamond hone. It sells for $50 these days, but I wouldn't hesitate to spend that again if I needed to. I am sick to death of cheap/bad tools. Say what you will about a workman never blaming the tools, but nobody builds fine architecture with a rock and bone.