Looking for a set of piston rings for 525 EFI
 

Hi,
i just rebuilding a Mercury 525 EFI .
The engine was rebuild by Mercury racing a few years ago and is bored to 0,030 oversize.
I need a new set of piston rings for one piston.
But i dont know what Pistons they are .
The normal rings from JE dont match, because the normal rings from the 502 are 1/16 1 /16 and 3 /16.
But the top ring is bigger then 1/16 the secund ring is small as 1/16 and the 3. ist smaller then 3 /16.
So they dont fit.
At the Pistons i found a few numers:

DRP 75
801SRC
2583

Can annyboady tell me what Pistons they are and where i can buy piston rings for that piston?

Thanks a lot

Christian