Whilst SIKKENS is a UK based company they are big enough to be listed in Cross references across the world (well at least from Greece {thanks Chris} to Trinidad West Indies )
You will have to check your ACTUAL bike to see which colours it should use as Yamaha used 2 whites, 2 reds, 2 blues thro the years.
For a plain white you can use Sikkens Kawa4000
If your colour official colour is not listed here please do three things:-
1] Give the official Yamaha colour name (see parts microfiche')
2] Give the SIKKENS number (from your paint supplier if he does not have it get a more professional supplier !)
3] Give your colour suppliers name {i.e.Du Pont} code as well to help your locals.