I assume you mean XRP with Ripple.
Ripple had a great rise to about 130billion. It now trades at 36.5 billion.
This indicator tells us, that a rise up to 3.81 $ is possible.
Still there is no money in this Business. The big boys are still trading with fiat money in the stock market and governments haven’t poured in money in crypto yet.
The following picture shows us an overview of asset classes. It is not up to date, even though it’s a from 2017 I guess. I found it on quora.
Credit
Answering your question “How big can Ripple get” is depending on what is Big for you.
But a few hundred billions in just one coin and company which is not dezentralized at all is pretty damn big in my opinion.
Short: XRP reached 130billion and could reach more. If it will have more reputation and a use case in the future, a few hundred billions are possible.
Once Billions are traded in the crypto world you will not trust your eyes because what you will see are prices and moonlandings of coins which you can’t imagine right now.
Most important: enjoy this time my friend, these days are historical
Hope this helps,