Here is a pic of the OEM gaskets used on the cats.
The top gasket is a round, "donut" style gasket. The bottom is a standard metal 2-bolt flange gasket.
Top 3-bolt “donut” gasket is Nissan Part Number: 20691-19U00
Bottom 2-bolt flange gasket is Nissan Part Number: 20692-1E810
Looks like you have the right part from Courtesy Parts.