Howdy,
I'm gonna disagree with my good pard, ButlerFord, and say the Marlin 1894C or Carbine. They can be found new for $400 or under and often under $300 used.
In general, the Marlin is more forgiving than the Rossi when using 38 special brass. Most of the reliable Rossis have been smithed, and that can cost around $100, so the makes the gun a bit pricey. Also, I think the Marlin has a faster resale potential.
Chocolate and vanilla, eh?
Adios,