I have an old one just like in the picture I inherited (no charge) and I wouldn't trade it for a brand new one made today even if you threw in two cases of beer with it. Very heavy duty and works well. With the added weight it cuts well and doesn't bounce. I also have a newer one too that I've had for years, belongs to my FIL, it's a nice pretty blade. But it doesn't work as well as my old one.
Sandblast or wire brush it and paint it, you'll have more blade for your money with the old one.
After posting I realized this was an old post. Sorry guys, don't know how to delete it. I'm guessing this thread will now be moved back to the current section. Well, maybe someone will learn the value of another piece of old iron.