If you look through the bass side f-hole, you should be able to see something like this (stamped on the back):
5.jpg
This picture shows the marking for a Silvertone H702 model (built by Harmony?), batch number 2615, manufactured in the second half of 1957 (my guitar).
The factory shut down for a period during the summer, so guitars are marked 'F' for 1st half of year, 'S' for 2nd half. Some sources claim 'F' for fall, 'S' for spring or summer, but I believe the 1st half, 2nd half story.
You may be able to find more information on the specific model at this site:
https://www.silvertoneworld.net/acoustic.html