Tall Allen may have another opinion, but it is my understanding that even the most sensitive (PSMA directed) scans available today are unlikely to reveal where the cancer is hiding in your body. Also, there could be many very small metastases (micro metastases).
Nevertheless, you can check on
clinicaltrials.gov whether something is available for you in a clinical protocol.
PS: It would be helpful if you would update your history since it is badly out of date.