Jamaica SG 78, 80/81, 83/89 Specimen 1919-21 part set to 10s from DLR day book

1919-21 part set of 10 to 10s (less 1d, 2¬Ωd), wmk MCA, opt 'SPECIMEN' (Samuel type D9 (1¬Ωd) or D12) and affixed to individual pieces from the DLR day book with m/s notations of the sheets sizes, the ¬Ωd, 1¬Ωd and 10s additionally dated "Sep 1920", "Mar 1919" and "Feb 1920" respectively. A couple of insignificant blemishes but a unique and important group. Ex 'Dubois' (Spink 14 Jul 2021, lot 508) and Hemmings (Cavendish 12 Mar 2014, lot 252), and illustrated in "The De La Rue Collection", vol 4, p. 4321.