Here's an Admiral page from the tvhistory website. It doesn't list this model, but it's hard to list everything.
http://www.tvhistory.tv/1950-59-ADMIRAL.htm
If I had to pick a year, I'd guess around 1957. People with better references than me might know better.
Connecting with the local radio club sounds like the way to start. Some radio collectors (like me) also collect & restore old TVs.
Phil