1/ You can find the exact partnr on one of the Yamaha genuine parts websites.
I found the original Yammieparts website quite userfriendly for this ->
Yamaha OEM Parts – Outboards, Outboard Motors
Your part can probably be found in the subsection 'bottom cowling' or so.
The exploded views of your engine on this website should make it clear.
2/ Then google search the obtained partnr and see where you can find the best/cheapest price.
Off course, if you 're lucky, someone here on boatmad knows immediately which part you mean and can help you out
Good luck mate !
T.
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