Yamaha part number for Reed PVC valve

I've been following the threads on this breather valve, and went to order one from MIkesXS, the site that has been referred to here. Unfortunately they are out of stock at the moment. I have asked my Yamaha dealer friend in New Zealand if he can source one for me, but he says that so far as he can tell the part number for the valve quoted on Mikes XS - #15-0677 - is not a Yamaha part number, and he can't trace it through looking through the records that he has available to him for XS650s. I don't suppose anyone can advise what the Yamaha part number is?

Mikes XS site sells an upgrade part that was never part of an orginal XS so no Yamaha dealer stocks them, there has been siteings of the breather on Chinese bikes but no part numbers.

I''ve got similar units made from Triumph air injection systems.

I'll match Mike's price.

However, I'm taking off to race and will be gone 11 days, so shipping will have to wait till I get back.