I think they still have diddling competitions at some of the TMSA festivals.

Worth saying too, that both Fifesing and Cullerlie, though happening in Scotland (and not in June!), don't confine themselves to Scots songs: there are usually guests from Scotland, England and Ireland (N and S), and sometimes from N America, as well as loads of enthusiastic singers among the general attenders. And they both have facilities for camping, whether tents or motorhomes/caravans.

Cornwall or Keith for that weekend of June 12th-14th? What a choice - and a distance between them!
You may need the wellies at Cullerlie!