You can also see a bit more about stables on Wikipedia. Stables include: PAX, USDC, DAI, TUSD, GUSD, USDS, USDT, BUSD, and EOSDT. This is not a complete list. As with many things in crypto, DYOR (Do Your Own Research).
For a 1:1 exchange of USDC, you will need to got to CoinBase, not Circle.
Note that while USDT was one of the first stablecoins, and is the biggest, it has a lot of controversy. There also seems to be a large amount of USDT that one must have, to convert to USD. There is also this thread on reddit. Thus, you may be better off with USDC, BUSD, GUSD, or any other that offers a 1:1.
To get an idea about how well USDT, TUSD, BUSD, GUSD, USDC, and other stables are trading, you may want to check out a site like Coin Market Cap.