You STOLE that stove, LOL!
The hopper is probably about the same size on mine, although I don't know for sure - haven't put coal in it yet. However, the hopper slopes down all sides to the stoker, so you can USE all 50 lbs. Other stokers have flat bottom hoppers that HOLD more coal, but a good percentage is NOT useable, it just stays in the corners and sits there.
But, if that's your only issue with the stove, you'll be counting your money all the way to the bank this winter!
Have fun moving it! If it only weighs 300#, pigs can also fly. I think just the bare stove body I have is 300#, less the doors, stoker, hopper, direct vent, and blowers!
If you can, take off at least the hopper and the direct vent blower to make it easier to handle (and the doors). I'd take EVERYTHING off of it, but if you have enough guys, you can save that project till you get home, as it makes a bit of a mess. GregL and I used his front loader with forklift tines to tip the stove down on it's side and slide it right into the back of my VW Jetta TDI Wagon, using some hardboard sheets as a 'slide'. Packed the rest of the parts in heavy bags and tucked them around the stove, tied it down with straps, and I drove it back from MI to IL.
Now I have the project of moving it into the basement......