Poxelles, why do you need to set the GWEI price higher than 99!! You can use
ethgasstation to estimate the gas price. For example, if you currently set the GWEI price at 38, then you will get your transaction confirmed within 5 minutes, which as per your needs is sufficient. But if you still want to set a higher price than 99, then you can install the
Metamask addon in your browser and enter the amount according to your wish.
Also you should post alternate currency related questions in altcoin section.