The Royal Oak in Edinburgh has a piano, which does get played sometimes, tho' you'll prob have to scoop a few people off the cover over the keys/change seats/remove Festival Fringe leaflets, etc, before you can get into it. It's prob NOT concert pitch but is playable after a Joanna-ish fashion. Somebody did do some ragtime stuff on it last week when I was in there.
If I'd known about the Swan in Sidmouth, I'd have had a go: next year maybe?