Jim,
I would not venture to guess how many (or, what %) of any trucks survive.
2% of the trucks in 1953 were 3800 series.
That 2% was 5,630 3800 series trucks.
That would make the total number of about 281,000 Chevrolet trucks in 1953.
By the way, the correct terminology for a 3804 pickup truck would be simply a 3804 pickup truck (there was only one bed size for each series of trucks - and therefore there is no meaning to "long bed" vs "short bed").
There was a different size of bed for each series: 3104 (1/2 ton pickup), 3604 (3/4 ton pickup), and 3804 (1 ton pickup); and, there was only one bed size for each series/size.
GMC 1/2 ton New Design trucks (47-55) did have a long bed and a short bed. I think that Chevrolet had long ed and short bed 1/2 ton Task Force trucks from 1955-2nd onwards.
