You are right Bill, it is a stock replacement. Same displacement.
Brook, look for a bigger bore (higher than 67mm). You may find "300cc" kits that are actually not really 300, but might be more than stock.
These kits can give you more displacement if they are bigger bore. Your stroke is 65mm.
Here is a displacement calculator to check actual cc depending on the bore:
https://spicerparts.com/calculators/...ent-calculator