Several non-U.S.-based members of one of my online Opera forums have reported in the past that that they listen to (and record) Metropolitan Opera streams on Sirius Channel 78 (The Met Channel) using the online service.
I searched the archives of that forum, and found reports from members in the UK and Australia who reported that they regularly listen to the Met channel using the Internet service.
They usually offer a 7-day (or longer) free trial - why not give it a try?
BTW - I have an online subscription, and plan to try it out for myself next month when the Met season opens while I am in Spain.