Thanks for all the feed back.
I'll definitely contact a machine shop. Unfortunately there are not many arround the corner with Model A engine experience.
@nkaminar, Yes the clearence of up to 0.024 inch is way too much according to the red book p 1-128. In general the bearings, piston pins and camshaft look great. The old oil was homogeneous and had absolutely no chips or cooling liquid in it. So far I found two more irregularities. The main oil line from pump shaft to chamber reservoir looks not good
Main oil line.jpg. It seems as parts from the iron cast has vanished. The piston 3 babbitt bearing has lost a part of the surface
Piston 3 rod bearing surface.jpg. I'm not sure how concerning the first one is? Definitely need to solve the rod bearing.
@Gene F, I used a metric micrometer an calculated the inches
@jerrytocci, good point, I'll keep that in mind
@CWPASADENA, do you think there is a chance to go on with the excessive piston cylinder clearence? If I conclude right then the compression will not build up as good and the oil consumption can increase.