The Stevens 325 was the first model of the design that is also available as the Savage 340. Many parts are interchangeable between them.
The Stevens 325 line was introduced in '47 and was discontinued in '50. (Besides the 325, there were 325A, B, & C variants later in production)
The Savage 340 version continued on for many years though. I know they were still selling them in the late 70s but I don't know when production ceased on the 340.
Your 325B was probably made in '48 or '49.
Value would depend on condition and even though it's a short-production model prices seem to still hang right with it's Savage340 sister. Up here in ND, $250 will get you a really nice one. A shaggy looking beater might sell for $150 or even less.
They have the same quirks as the 340.
The trigger isn't the best...it's just a bunch of stamped sheetmetal parts afterall.
The single, rear lug bolt isn't the strongest action ever made but it's perfectly adequate for the .30-30.
They are usually pretty accurate little rifles though once you get the hang of their usually funky trigger pull.
They're not real pretty too look at either, BUT as a cheap bargain shooter you can't go wrong with one.