I purchased a very inexpensive postwar 464 sawmill with the intent of improving the operation and appearance.
Fortunately, the dust separator was not missing, just the handrail. The sawmill actually ran, but the noise was unbearable!! I expected this and and replaced the original motor with a canned motor/gearbox assembly. I made a motor drive belt using flat elastic, it works quite well and slips if something jams. The speed is just right at 12vdc.
I did not like the gray base and the plastic look, so I painted the base light brown, the roof silver and the building white. I primed and weathered the dust separator. I made a new handrail with brass rods I had. The wood grain on the base shows up much better with the new color.
I wanted to add a circular saw similar to the current sawmills, but there isn't much depth available in the front of the building. Then I remembered saving a couple of electric toothbrush heads due to the right angle drive. I had a servo motor with burned up electronics, so I used that, the toothbrush head and an old clock gear to make a saw. It runs at the right speed around 5vdc. I still need to add lights, and couple of operators.