Hello Matt,
Thanks for your email and the link to the bowcaster pics.
Mystery Solved!
The original bowcaster was not based on the Monarch Supreme, but a skeleton stocked crossbow designed and made by me for the 'SinglePoint' Company in the UK.
This company developed and manufactured the first red dot sight, invented by a Swede, Neils Ruder, I believe his name was, in the early '70s.
It was expensive and well made and aimed at the military market. They approached me at that time to develop a military style crossbow to take their new sight and which could be used to demonstrate the speed and efficiency of the new technology sighting system.
The bow was made in the same way as the Monarch Supreme; die cast aluminum and nylon coated.
Probably 12 to 15 thousand of these crossbow were sold during the early and mid seventies, mostly in the UK. In the latter years they were sold to the civilian market by an off shoot of the 'SinglePoint' Company.
I imagine very few were actually sold in the US.
I hope this answers your questions on the origin of the bowcaster, I am sorry it has taken so long to get to the eventual facts.
Kindest regards Bernard Horton.