I just loaded some 45 Colt with a container of Unique that I inherited from my Dad. The powder dates from - at least - the early 90s, possibly some time in the 80s. The powder worked without a problem.

I also have a lot of old primers, including some LR Primers from RWS, a West German company. The package is stamped 1973. That’s what I use in my Krag reloads, and they work fine too.

If nothing looks off (including the smell), I would give it a try.