I've run a Vbulletin forum which consumed a full half TB of bandwidth per month on this shared hosting service:
https://dreamhost.com/hosting.html
They are inexpensive, but customer service is a bit slow and they won't be GEI's forum administrator. They do manage the actual database and web server administration, That said, it is kind of a "do it yourself" operation. But you can't beat the price and they've been in business a long time.
I assume your backend is Mysql? My quess is, all you'd need to do is unzip your forum software, dump and upload your database, then enter the appropriate paths to the web server and database servers with regard to the respective configuration files, and it should run fine.