The very last Postage Due stamps were taken off sale in the General Post Office in Barbados in 2010 and there are no plans to issue any more. I know this as I actually got the last two sets from the Philatelic Bureau when I was there in August 2010 and the very lovely Angela went downstairs to the general counters to see if she could rustle up any more sets for me!
Barbados Postage Due D1
Barbados Postage Due D2
Barbados Postage Due D2a
Barbados Postage Due D3
Barbados Postage Due D4
Barbados Postage Due D4a
Barbados Postage Due D5
Barbados Postage Due D5a
Barbados Postage Due D6
Barbados Postage Due D6a
Barbados Postage Due D7
Barbados Postage Due D7b
Barbados Postage Due D8
Barbados Postage Due D9
Barbados Postage Due D9a
Barbados Postage Due D10
Barbados Postage Due D12
Barbados Postage Due D13
Barbados Postage Due D14
Barbados Postage Due D15
Barbados Postage Due D16
Barbados Postage Due D17
Barbados Postage Due D18
Barbados Postage Due D19
Full sheet of Barbados Postage Due 1951 1c Green SGD4a
Full sheet of Barbados Postage Due 1953 2c Black SGD5a