Is there an actual rated thrust for a Cessna 172 engine at takeoff power?
A fixed pitch prop will develop maximum thrust somewhere between static and maximum air speed depending on its pitch. Finer pitch will give better acceleration from a standing start, more coarse will give more thrust at cruise.  People generally do not quote thrust numbers with props, charts calculating weight and weather effects on performance are far more important than "thrust".

However, if you want to know, do it the same way James Watt did, either by lifting a weight, moving a weight, or lifting AND moving a weight.  Watt knew just to take the first meter, where air drag was negligible.  For a Cessna, I would take the first 100 feet, release the brake, and hold a stop watch.  As John K said, it should be 500-600 lbs.  F=ma.

Just keep in mind, the key to those performance charts is that weather conditions have MAJOR effects on power and prop efficiency (prop thrust), this is what you MUST be aware of before takeoff.