TC ... back when we were having the Crappie.com tourneys on Watts Bar (2000-2005), the owner of Eden Marina sold "tuffies" (Fatheads) and there would be the occasional "Rosey Red" in the mix. But, I'd have to go back a few more decades to remember getting "Baltimore minnows" (goldfish) from that area. But, back then we were primarily fishing for Smallmouth, and usually brought our own minnows (Fatheads). We only bought the Baltimores one time, and that was so we could catch bigger Smallmouth than what our Fatheads were catching.
You're most likely going to have to go to a pet shop or Wallace World to get goldfish, and even then they may not have the olive-green "Baltimore" version.
... cp