To get a pretty good estimate of the deck height w/o using expensive tools, you can simply bridge across the bore of the cylinder you're measuring w/a straight edge or machinist rule on edge and use feeler gauges to measure the distance between the straight edge and the piston top, w/the piston at TDC. Measure over the axis of the wrist pin to eliminate the piston's rocking in the bore caused by the piston to wall clearance.
Measure the combustion chamber volume by using an old CD w/the plating scraped off w/a razor blade drawn across the plating backwards (opposite way than if you were going to "shave" it, if you follow me). This flakes off the plating so you can see through the CD to tell if there are bubbles. Or you can use a piece of plastic like plexiglass large enough to fully cover the chamber.
It has to have two holes- one for introducing the fluid, the other to allow the air to escape. Usually, the one hole in a CD is large enough to do both.
Then "glue" the CD or plexi onto the spotlessly clean head surface using vaseline or grease. Leave a spark plug in, and level the head evenly.
Then using a large syringe and rubbing alcohol (has low surface tension) dyed w/food coloring, fill the chamber until completely full, counting the amount of alcohol you used to fill it.