Your network provider supports multicast traffic but your provider network does not. You want to
allow multicast hosts outside of your network to receive multicast traffic sourced within your network.
How would you satisfy this requirement?
Use MSDP peering with your provider.
Use AutoVPN to connect to the remote hosts.
Use an MP-BGP session to your provider to pass multicast traffic.
Use automatic multicast tunnel gateway at the edge of your network.