do any manufacture produce MKT HO scale locomotives besidedes Stewart?
atheran did
Athearn did the SD40-2
Atlas did the U23B
As stated earlier,
Athearn did the SD40-2 in a dummy and powered unit , they also just released a RTR GP38-2 in Katy Green and yellow number 308
Atlas has released the U23B in all three road numbers 350-352
as well as two GP40’s numbered 175 and 171 as well as a no number unit, these have the dual mode decoder. They have also released a GP7 or GP9 (cant remeber which) in katy red from the Atlas classic line. I believe they are releasing another katy red engine this summer.
Stewart hobbies has the S-12 switcher in red in two road numbers
Model Power has a Alco unit that is fictional, released in green and yellow. This unit was never part of the Katy stable, but it is in MKT colors. You could probably pick this one up for about 20 bucks
There are lots of freight cars also out there by almost every manufacturer. My favorite company is Atlas, as they seem to take the most interest in the Katy. I have many of their models and find them to be GREAT!
Hope this helps
Dave