The OEM part number is; Kawasaki TAP-ASSY,FUEL Part # 51023-0032
Here is a link to the part at bike bandit new from kawi. Keep in mind that when I ordered my OEM gas cap from kawi through bike bandit I had to wait about 45 days before it actually hit a US port in cali.
https://www.bikebandit.com/oem-parts...685&sch=706597
Bike bandit is one of several websites where you add a motorcycle to your "garage" then you can browse the parts diagrams to find exactly what you need.
Add the bike to your "garage", click "my garage" at the top next to "my cart", click on the bike you want listed there (this will bring up the parts diagrams), from here click "fuel &air", then "OEM Parts", finally "fuel tank".
From here you can see all the internal parts of the petcock to replace individual things if you want or just order a whole assembly.
Learning to navigate parts diagrams is super helpful and you can use it across all vehicles.