Closed chambers gone bad… that’s a wrap
My two cents- take it apart and go over everything with a fine tooth comb before spending any money. Pistons do not appear to be hurt. Some race engines have been purposely designed to barely kiss the head chamber similar to what you think yours is doing. Rod bearings, ring lands, and piston crowns will tell the tail once torn down and cleaned up.
Now if you are looking for an excuse to go stroker then by all means go for it. Regardless when you mock up bottom end this time you must measure how far out of the bore the piston is by rocking the piston in the bore both against the thrust side and opposite side. The looser the bore the more piston rock can happen. Get your deck bridge and dial indicator out. I would also measure the head gasket after compressing it by pulling the heads again.