At least one handy person on this forum has built a really top notch one out of fiberglass that had awesome fit and finish. I tried to find it but came up short.
This question has been asked since 2016 and I’m not aware of any aftermarket cover for a Yamaha to date.
Aftermarket is only interested in Polaris and CanAm for the most part. Yamaha pretty well comes last if ever and Yamaha is at the bottom for OEM accessories offered.
Pretty much we are left to build it ourselves or convert it to work.
I would not expect anything to come along in the world were living in now. We couldn’t even get anything when the economy and supply chain were good.