Forgotten seems to be the operative word. Do you have no information at all? Was your tape a pirate copy with no title or other info attached?

There was an LP by a UK group called Amity on Red Rag Recordings RedRag RRR001 (1976?), it seems. There's even a copy listed for sale at http://www.vinylrecords.co.uk/folk.html ... for £100 ...

Red Rag also released LPs from Stan Arnold, The Calico String Bandand Bully Wee among others, apparently. The label doesn't seem to have lasted long. I suppose it's possible that someone bought up the back catalogue, but it seems to have sunk without trace.