I haven't seen them on available for sale lists for a couple of years, either. Probably your best bet would be to contact the individual breeders that list the mints and ask if they are also breeding goldens. Sometimes, they will have some frogs in too low numbers to list publicly, but would be willing to sell a few. You could check with Saurian, Black Jungle, Quality Captives to see if they are breeding them at all, and perhaps get an idea as to when they might become available again.
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Patty
Pahsimeroi, Idaho
4 D. auratus blue
6 D. galactonotus pumpkin orange splash back
7 D. imitator
6 D. leucomelas
6 D. pumilio Bastimentos
4 D. fantasticus
6 P. terribilis mint and organe
4 D. reticulatus
4 D. castaneoticus
2 D. azureus
4 P vittatus
2 P. lugubris