Brian, without the serial number it is hard to determine when made.
Bar action is when the "action" is before the hammer, the mainspring is recessed in the long finger of the side plate.
All the workings are shown in the picture attached.
Hope this helps you.
https://ibb.co/ynLG6pD7][img]https://i.ibb.co/cczM6wPV/3-bridles-3-hammers-2-copy.jpg[/img