An OX Fina investment is a very risky one. The price of this coin has hit rock bottom, and for good reason. The developers seem to have abandoned the project entirely, leaving many disappointed investors in limbo. The OX chain was originally intended to be a secure place for storing financial data.
Their Ethereum based token which was distributed to investors was meant to provide a recurring payment to the token holders for any fees which were collected by the platform. Some are talking about a community takeover of the coin which while not impossible, but I find it a very unlikely scenario.
If you wish to buy OX Fina for the small chance that maybe it will be taken over by the community and developed again then it is still available on a couple of exchanges. While there are a few pairs for USD and LTC the highest volume one is for BTC, and due to the low trading volume of this coin it's probably your only option should you wish to acquire it.
Normally, I wouldn't advise you to ever store tokens on an exchange, but since these are not worth much I might not even bother moving them should you have them. However, this is an ERC20 compatible token, and so you can store it in any wallet that supports Ethereum assets such as My Ether Wallet.