I think 'gulag' is used either to refer specifically to the Soviet camp system, or is used metaphorically in reference to some other camp system, in order to emphasize a similarity with the Soviet system. So I don't think there is any need for two articles, since the word and the acronym have the same referent. And to fall back on convention, the book 'The Gulag Archipelego' is always spelled with 'Gulag' the word, not 'GULAG' the acronym - suggesting that the word is correct even when referring specifically to the system. - Tim
On further reflection, I don't think gulag is even an acronym. It is a word made up from parts of other words, which was common practice for the Soviets. Comintern is another. Laogai is a Chinese example, I think. Orwell's 'Ingsoc' is a parody of this practice. I believe it was Orwell who wrote about this practice, claiming it was an attempt to reduce language to mere symbolism devoid of any semantic content by divorcing words from concepts. - Tim