You'll be able to find one easily and cheaply. They are one of the most common LF lenses out there, and they often go for peanuts ($40 or less).
I've never been disappointed with the performance of my copy, even with its air bubble. It is plenty sharp for me at any aperture. I once made 20x24 color enlargements shot at f/5.6 with this lens, and I was very happy with the sharpness.