In case you haven't seen it yet, Key Models has announced production (pending enough reservations) everything from SD7's through SD45T-2s. Examples would include the SD7 SD9 SD18 SD24 SD26 SD35 SDP35 SD38 SD38-2 SD39 SD40 SD40X SD40A SD40-2 SD40-2W SD40T-2 SD40-2S SDP40 SDP40F SD45 SD45X SD45-2 and SD45T-2.
http://www.keymodels.net/id34.html
The first locomotive will be the SD40-2.