Practical advice first...
get a loading manual. They have lists of powders like what you seek.
Last time I was at jhara they had titegroup. $40 per lb.
Grab a bottle if you can. A little goes a long way.
As you already know, what you actually end up doing is limited by what is available.
Hook up with a friend that reloads already. Much easier to learn like that.
There is a huge gap between basic mechanics and actual execution.
...
45 acp. :-)Ww231, hp38, wst, be, trap100, red dot, clays.,,,,, for the 45acp most any very fast powder will work.
Same list for 38 spec
357 mag...h110, ww296, blue dot,,,,slow burn powders will get you that magnum effect.
....
Btw today I am adopting my first dog. A totally new experience.
Since I was at the humane society in kaimuki, I stopped at jhara.
They still had titegroup there.