The value of a Remington Model 11-48 (introduced in 1952) in 28-gauge will be predicated upon its condition, and whether its barrel is plain or has a ventilated rib (it was available in both configurations).
Accordingly, the approximate value might range anywhere from $345-420 at the high end to $161-196 at the low end for a plain-barreled gun, and $374-455 at the high end to $161-196 at the low end for a vent-rib-barreled gun.
Hope this helps.
Good luck, and good shooting!
