Pistol
. . . new used just powerfull for oregon. a pistol
Original post says pistol.
Original post also says powerful.
And $350 . . . so . . .
Powerful starts at 9mm and goes to .45 calibre.
At $350, a pistol, somewhere between 9mm and .45 . . . hmmm.
Well, a Ruger Blackhawk in .357 would be right around $350 (used, in good shape).
Taurus does a reasonable .357 revolver in that same price range.
Something in a used S&W .357 will run just over $350.
Also at the used counter, you may find S&W 59xx or 69xx 9mm pistols in that price range.
If the gods smile on you, it's just barely possible you could find something in .45 ACP at the used counter for $350 -- but if you do, check its teeth and toes, it may have problems.
Now, you can also get (new) a range of Taurus pistols in 9mm, .40 cal, and .45 cal, all in that $350 bracket.
In your shoes (depending on lots of information I don't have) I would probably look for a .357 revolver, starting with the Blackhawk. My thinking is that the .357 can eat the same food as your .38 spl.
I have, from time to time, seen used Ruger (Blackhawk, GP100, SP101), S&W, and Taurus revolvers in .357 in that price range.
If I were going to say more, I'd need more application information to frame the context.