As
doobry is also listed by a few dictionaries, it should be allowed in future. But that presumably means we should also accept the alternate spellings,
doobrie and
doobrey. Paradoxically, it's the words that are very seldom written down that may get multiple entries in our word list, because nobody's certain how they should be spelt.
But what about
doobries? As the plural of
doobry it should be accepted, but as the plural of
doobrie it's not allowed. There's no right answer, of course, but I'm leaving it out. The three singular variants will be accepted, as rare words.
The earliest citation in the OED is from 1977, but the
entry in Green's Dictionary of Slang has this note:
[orig. in the army, the term gained a new lease of life thanks to the DJ and TV performer Kenny Everett, who used it frequently in the 1970s–80s]
And indeed, the OED's 1977 example is from the back cover of a book about Kenny Everett's character Captain Kremmen:
Join our hero inside and feel that rare thrill of electric excitement runnin' up yer doobrie.
Also from 1977 was the Ian Dury song
Common as Muck, including these lyrics:
I'm not Nellie Melba, you're not Nellie Dean
We do our best endeavours to keep our doobries clean
Because we care!