I decided today that I really want one that is a wool cooler with a waterproof, breathable outer. Not necessarily even waterproof, just slick.
I work horses, put a sheet on them and turn them out....they roll....sheet gets really dirty (especially if it is damp). So if the cooler had an outer layer I wouldn't cringe as I turn them out.
For what it's worth I don't turn them out in wool coolers, I would, however, prefer them for when they are still damp after working.
Bucas Power Turnout is what you are looking for but not a wool liner. I love these sheets for the same reason. I got an amazing deal on one at a 1/3 the price and barn worker chose the shortcut method of no lead with horse in turnout. He spooked, blanket trashed beyond repair. : ( I don't have $300 to buy new. I know where you can get a 78 or 81 from clearance. If anyone knows of a 76 on clearance, let me know.
Yes, the Bucas sheets with the stay dry lining work really well. I am on the hunt for one in size 72" right now.
Also, if you can find a turnout lined in Coolex they are lovely! Well used in the UK, they are hard to findin the US Dover was importing them under their "Riders" brand but it looks like they no longer are.
The other thing I wish "they" made was a tail cover with a gusset for our horses that hold their tails up a bit.
I have a couple that naturally hold their tails out and end up sort of rubbed by the end of winter.
Sigh, my dream blanket? Gore-tex lined....wish Classic Coverups was still around
Bevals used to make/sell these. Heavy weight quilting and Gore-tex. The first 400 smackers I had "extra" was going to go to one of these. I still don't own one. Not sure they exist anymore, but Bevals New Canaan store would know.