Make your own. Bottle of RAW kombucha, 1 cu. brewed black tea, 2 tbsp. of sugar, put all in your kombucha fermenter and let sit 3-4 weeks until scoby forms.
Then use 1/2 cu of that liquid + scoby to make kombucha. I do 1/2 gal H2O. bring to boil, add heaping 1/2 cu reg. sugar + 8 regular black tea bags. Steep til room temp. Add to scoby/starter. Ready in 5 days or so.