This is one half of a pair of trucks - i do have a copy of the photo with both in so will dig that out but cant find the original at the moment.
Images have been scanned through glass as didnt want to damage the images, so a bit fuzzy
Wickham Type 11 Saloon Inspection car with Meadows petrol engine and reversible seats circa 1929
This is a Wickham Railcar built for India. Works No. 494 - shipped from Ware 29th January 1932. 2'6" gauge. Used on Kalka-Simla Railway for Inspections. Preserved at Railway Museum in Delhi
Further up to date image here https://www.flickr.com/photos/peamasher/16598919276/in/photostream/