453,459,463, and 464 were used quit often on the Silverton mixed trains. Before and during WWII the mixed trains would have been more freight then passenger. But after the war when there was more tourist traffic, then freight they could be seen hauling a long train that was 90% passenger cars.
There is a great shot in American narrow gauge of 463 on the high line headed up grade with at least 10 cars. The first two cars are a high side gondola full of something, and a caboose, the rest is two baggage cars, and six coaches.
the tail end of the train goes around the curve and you can only see a little bit of the 10th car so there could be more.
Hope this helps.