Orange Free State 1890 1d Ovpts, Tunisian Archive Specimens

1890 1d on 3d, 4d ultramarine (SG 54&57), each handstamped "SPECIMEN" type TUN1 in black (by the Tunisian Post Office as the Receiving Authority applying the handstamp to their distribution from the UPU). Affixed to small pieces of ledger sheet from the Tunisian UPU specimen collection. Interesting pair proving distribution of these Type a ovpts through the UPU.