Aside: my acess to daily NGL pricing sites has vanished. I guess I should have expected that; I wasn't paying anything. There are several possible alternatives but the fees are not cheap." -RossA
Perhaps one of the NGL pricing sites would be willing to make data available 'free of charge' once a week or once a month with a delay of several days or a week or so. Especially if you RossA explained to them your intention to post here.
It might furnish the data provider some interesting advertising. Folks from the financial sector are reading this site. The midstream sector may be attractive for those looking for dividend and growth opportunities that are uncorrelated to the fortunes of oil and oil e&ps.
Older data would be fine for most of us cheap retail investors. ;-)