Hey .308,
Calm down. Ruger made thousands and thousands and thousands of SP-101s. They aren't at all rare. They aren't at all collectible. They aren't at all hard to find. The reason they quit making them was that they didn't sell well. Again, really bulky, and terrible terrible triggers.
The 1894 Marlin, in .357, is a fantastic little gun. With factory ammo, and 158 grain bullets, you will be getting 1,250 foot pounds or so of energy at the muzzle, and about 725 foot pounds at 100 yards. (In other words, at 100 yards, you will get 200 foot pounds of power MORE than shooting somebody point blank with a .357 pistol! Nough said.)
In the heavy woods of the East Coast, lots of people use these to deer hunt. They are good deer stoppers, so long as you keep your range at or under 100 hards, and make a careful broadside lung shot, avoiding the shoulder bone. By the way, I thinks Garret and/or Bufffalo bullet co. sell loaded rounds, using compressed powder charges, which they say are safe for use in the Marlin, and deliver energy that is just a shade under the 30-30 Winchester. (Pretty expensive though.) You could also use Core-Bond, 180 grain, hunting loads.
And, Hornaday has just announced that it is going to sell the LeverEvolution rounds, for use in the .357 magnum Marlins, obviously for hunting.
Best regards,
Mannyrock