I can't comment on the others because I haven't heard of them but Hartford is still in business thier web site is http://www.hartfordpr.com/ I'm not sure of others for "Craftsman" type kits since I'm not sure what would be classified as one.
Jack
What scale are you interested in? For 1:20 narrow gauge kits, there is a company called Northeast Narrow Gauge in Wiscasset, Maine. Their web site is http://www.nemodel.com
Hartford is the only company you list that I have heard of because I have not been into G-scale that long.
Sierra and Trail Creek still advertised in the latest Finescale Modelrailroader if my memory serves me correct.
Done Google search on any of them?
Have fun with your trains
I got the 30 foot flat car from Big Train Backshop
Contact info is slotrains@charter.net
These people have other wood kits and come without trucks or couplers. They do have the brake wheel, air tank, truss rods, rivits.
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