Schneider in TIC2 tells us that 504 had PZIII's numbered 01, 02, 03, 04 and 05, so the turret number is in the range we expect.
I think these are 504 because of the use of the rhomboid; the dark stripe within it (but no 's') is consistent with 504's Tigers. The size and position of the 'St' is consistent with the company numbers used by 504.
The number '02' is in a shade, size, font and position consistent with 504's Tigers, but no other unit comes to mind.
I don't think they can belong to anyone but 504.
As an aside, Schneider also lists Tigers numbered 01 and 02. We have no photographic evidence for these Tigers and use of duplicate numbers would be most unusual.