Could you please post links to the listings, Alastair? Something sold in the last 5 years is much more important to today's collectors than something sold 10 years ago or more. And it's important to know which independent authenticators examined them, if any.
If anyone wants to see them go to rr auction past auctions and type nirvana then you can click on the items and see dates and prices and some have photos.
Please provide a link to the page each image is on, even if the image isn't showing. It will say when it was sold and if it was independently authenticated, who it was.