A fan wrote in to say they found Thistles from 1962 at a consignment shop in Mountain View. Good find. Keep your eyes peeled. I'll have to check the slide archive for any record of it.
Another painting from a similar vintage seen on the blog here: http://ruthdickerpaintings.blogspot.com/2018/07/a-nice-piece-from-1960s.html is semi-actively looking for a good home. Reach out if interested.
It looks like somebody snapped up a very fine piece at Auction last fall: https://finesf.com/lot/ruth-dicker-the-forest-der-wald-1982-4047462.
Finally, Les Arbres dans L'Hiver continues to be for say on ebay, but the price might be too high. We'll have to keep watching that one.