They still make H380 and US869. Its listed on Hodgdon's Website. H870 is not listed though. With H1000 and 50BMG available as well, 870 isn't needed. If you really want H870, its available from gibrass.com as a pulldown powder, and Alliant's 8700 is also available.
Buy American, it may be your own job you are saving.
UTU, TY&E Service, BNSF