Dual WAN Port Router

We have 2 separate links for Internet and email.
1. Our email goes through an isp in our country.
2. Internet access is through VSAT

At the moment, the router we have has a single WAN port and is being used for email. VSAT is connected directly to the proxy server.

I am thinking of buying a new router with dual wan port so that I could configure one port for email and the other for internet.

if someone out there had been in a similar situation, please assist me on hoe to configure this.