Electrical mast retrofit flashing kit for roof penetration

Hello,

I have a query concerning identify appropriate electrical mast flashing product for a renovation work. The roof and interior ceiling shown in the attached picture requires repair work due to water damage. It seems water is entering the area via the penetration in the roof where the electrical mast is installed. The electrical mast on the roof is installed very close to the wall and on the step flashing. This seems to be the area where water seems to penetrate and cause damage to the interior ceiling.

Is it recommended to re-locate the existing electrical mast to a location further away from the wall and then repair the roof and ceiling assembly, and then install an appropriate electrical mast flashing product OR Is it possible to repair the roof and ceiling while the electrical mast is still in place. Would an electrical mast flashing product be available for such an installation where the electrical mast is installed so close to the wall on the step flashing, because usually the flashing product would require few inches of clearance.

I'd appreciate your comments and recommendations.

Thank you.