Winchester still makes it in seasonal (limited) runs--albeit @ $40.00 a box (20 ct).
I have been reloading it for about 12 years, mine was also a grandpa's gun.
Mine still prints 3/4" for 3 shots and 1-1/2" for 5. It's a 1951EG model, looking very similar to yours.
My favorite loads are 38 grns of H-335 under a 150 grn round nose (very accurate) and 37 grns of IMR3031 and 165 Speer Grand Slam (most accurate).
These loads are worked up for my gun and show no signs of pressure, velocities run around 2600 fps for the 150's and 2450 fps for the 165's.
I have not taken any game with these, but they are more than adequate for deer & black bear sized game.
Attending some gun shows might net you some good prices on ammo, but it can be hit or miss.
