This lot was recently sold on E-Bay; priced at around A$60 (26 Sep 03).
Here's what the seller says about it:
New Guinea 1937 Coronation Set of of Overprinted "SPECIMEN" Diagonally Mint Never Hinged
S.G. Nos. 108/110.
I am not sure as to the origin of these but I must assume that they were made by some foreign receiving post office.
Have any of our members any knowledge of this set?
Has anyone seen a similar set?