Small ISP here: Can we become a stream relay?

We have about 400+ customers in our little network, and I'm sure come Conference a bunch of them will be streaming the same data.

Is there any way we could host some sort of IceCast/ShoutCast type relay server in our NOC? That would greatly reduce the load on our network as well as the Church's.

you may be able to find some help in this forum - http://tech.lds.org/forum/viewforum.php?f=28

Most of the forum users here are church members who use technology locally for their church assignments – I'm not sure who might be able to answer your question, but I don't expect that you would get any official response here. Sorry!