Greetings from Canada,
There are two ways we can do this. If you have access to both forums we can make it insert in the database when a new post is made on the forum you want to copy from. If not - we can parse the original forum and make it paste to the new forum. I can write you a php script that does that, all you need to do is run the script I provide on a scheduled time (cron job) and it will copy the forum for you!