The IC 2-8-0s were received from Baldwin with the round sand dome, per the Bachmann design. The IC sent them to the Paducah, Ky. shops and put the rectangular sandboxes on.
Looking at the photo a previous poster linked to of an SP 2-8-0, I would have to agree with the statement that the only thing the Baldwin shares with it is the wheel arrangement. The cylinders, for starters, have the valve chambers mounted inboard of the crosshead, the boiler is a flat-top cylindrical design, the domes are in the wrong places, the cab is wrong, etc., etc., Furthermore, the firebox on the Harriman loco sits between the rear drivers. The Baldwin loco has a wide firebox which sits above the drivers.
Regarding lifting vs. non-lifting injectors: most railroads and loco builders switched to non-lifting injectors because they are inherently more reliable in delivering water to the boiler. They work on a lower steam pressure, as well. Trust me, you haven't lived until you've tried to get a cranky lifting injector to "pick up" when your water level in the boiler is below the lowest try c*ck! Very scary!
It should be noted, however, that lifting injectors were placed outside the cab as often as not (the above referenced SP loco is an example). The actuating lever on some of the later versions could be operated with a reach rod as well as directly - see the design and placement of the injectors on a USRA Light Pacific. One reason for having it in the cab, though, was to make it easier to whack it with a hammer to loosen it up when it refused to pick up. :-) It also kept them from freezing up in cold climates.