Sold by Bukowksis (Stockholm):

19 april 1972. Type-written letter from the author to a reader. Folded, some sun-fading, light foxing. Page size: 22.5 x 15.5 cm.

http://www.bukowskismarket.com/items/328088-brev-j-r-r-tolkien-egenhandigt-signerat-dat-19-april-1972

Sold by The Manhattan Rare Book Company:
Letters and books- including an autograph letter by J.R.R. Tolkien and two autograph letters and an autograph note by C.S. Lewis- from the collection of Robert W. Burchfield. [...] Autograph letter signed by J.R.R. Tolkien to Burchfield dated June 11, 1972 and written from Merton College, apologizing for not [...]