Got my first deer with my dad's 195 Mossy in 1974. Here is what I know about 'em.
They made many model variations over more than 40 years, and the guns were also sold by Monkey Wards, Sears, Western Auto, ect under their own brand names.
The 1xx series is older than the 3xx series. The earliest .410 was the model 83, this became the 183. The last two numbers indicates the gauge; 83=.410, 85= 20, 90=16, 95=12. D models had choke tubes, K models had Mossberg's version of the Poly Choke, the C-Lect-Choke.
As usuall with common "working guns" these do not have much resale value. An interesting and somewhat rare Mossy was the 595. With it's 18 inch barrel and 4 round box sticking out it is pretty mean looking.