Need help with piston bearing

Is there a higher quality roller bearing to fit what I think is the 12mm wristpin. I needed to
replace a piston and head because they were running into each other ( about an 1/8") around
the outside edge. The piston I got from DAX has too big of a wristpin. so now I guess I have
to find the bigger wrist pin AND a a roller bearing with the same ID assuming that the OD
is the same to all the cranks. Does anyone have a bearing chart for the different fits ?? TIA

I would have returned the engine before I took it apart if the piston was hitting.

Was your old wrist pin using a bearing or a bushing?

__________________
If it ain't broke, and you mess with it long enough, it will be.

Well, my big theory is that after awhile the crank might have stretched a little and
the upper crank arm was sliding side to side on the roller bearing itself.
The engine is an old powerking 80 and I'm trying to figure out how I can use the 12mm
pistons from DAX and just replace the 10mm wrist pin and bearing. I did a search and read
through a bunch of posts where other people had the same trouble and replaced the bearing
and added shims.
I guess I'll try that ... or give up and buy another engine, but no one has just the engine
in stock right now. Thanks

Yeah, it will have to be a new motor. The bearing cage slops around inside the crank
arm more than I want. Here's some pix though :