You must provide a detailed description of the weapon, the magazines, the weights, any boxes, the finish on all, etc.. Without pictures or a hands on examination the best range I can estimate would be 100-1000 USD, give or take.
If you Google "high standard supermatic trophy" you will find auctions that have sold this gun for the high $600's. It is valued up to $1000. based on condition and model.
1966
1965 to 1968 --about 45 years old
10-1000 USD or more depending on specifics
The Supermatic Trophy used the ML prefix from 1951-1953.
100-1000
Check out John Stimpsons's website.
1943
32 years old
Not really
42 years old.
47 years old.