Don't see any reason to reblue it, but you can do the woodwork . You have to remove that screw in the forend if it has a hung trigger because the screw fouls the trigger mount on a No4Mk1/2, No4 Mk 1/3, or No4Mk2
Easy way to check, remove the trigger guard, if the trigger comes with it you have a No4Mk1, if it doesn't you have the other. Loosen front guard screw first and then remove rear screw. Assemble in reverse order beecause the front screw puts tension on the guard and can make the rear screw difficult to temove.
Restoring it to military configuration would involve rebarreling and thats way too much to spend.