That's what I thought you'd find. It depends how far you want to go with it. If it needs bored and you need pistons anyway you might as well get the high compressions ones. Egge still makes them. What rocker arms do you have? Adjustables? If so you can change to a solid lifter cam like the original engines had with new lifters and pushrods. But, nothing wrong with a hydraulic and lots more choices.