Head Clearance Measuring Tools?
If you purchase a measuring tool designed specifically for measuring head clearance that is all it is goog for. Buy something more versatile.
You will need a 0"-1" depth micrometer for measuring stroke and squish band depth. You will also need a 0"-1" micrometer for measuring shim thicknesses. You should be able to get them both from Industrial suppliers or good tool stores for less than $250.
Ed S