I've managed to talk another contact of mine into setting up a new HF feed for us, this time it's NYC on 8918. This freq covers the L451, L452, L453 routes north-south, and the M325-331 routes east-west to/from Bermuda. The freq is typically active from around 1200z to 0000z as a general rule. Don't expect to hear much on it outside of those hours as they usually drop down to 5550/5520 and unfortunately this is a fixed frequency feed.
Some days the frequency will be very quiet for traffic as local weather patterns can mean that the routes the freq covers are not in use that day, but equally it can work the other way round too.
You can download the PDF enroute chart for this area from this link -
http://aeronav.faa.gov/enroute/04-05-2012/WATRS.pdf.
Thanks to Chuck for providing the feed and thanks to Dave for the relay and archives.
http://d.liveatc.net/hf_ck_8918
