Alliant Power Pro LR4000 is available now and does the same thing. Velocities in the Alliant manual run right with RL17 and it is also a ball powder like the Hogdon stuff. There are several different burn rates. I think they are designated 2000, 3000, and 4000 series.
The 4000 has approx the same charge weights as RL19 according to the Alliant website.