Does it have a date on the barrel (on top just behind the sight). ? Should have the flaming bomb symbol as it does not look like the barrel is cut off.
Has to be Springfield Armory with a 21 date.
Yours if 500 higher than mine (4/21) so you can call it 4 or 5 of 21.
Value wise $300 is a decent price. Could be had for a bit less like $200 dependency on seller.
Keep in mind not much (current) collector value due to the drilling mods.
Its a nice sporter stock and setup. When the good ones get rare enough, then the sporters will shoot up as you can "fix" the holes and have an OEM 1903 (far better than recovered drill rifles).
Particularly important is not to cut the barrel off. You can't get new barrels for guns of that era (1903A3 yes, but not those)
note: I am also in Alaska, and yes its a great moose gun and a Grizzly bear in and emergency. Mine is documented for 5 of those (life and property defense in the 50s). Let me know if you don't buy it.