First, it was manufactured by Stevens; they bought the rights from Browning. It could be close to 100 years old but at least 75. They sell for 100-200 dollars.
If it was manufactured prior to 1968 it probably doesn't have one.
Western Field model m5500 20 ga was manufactured by Savage Arms
Gun Digest.
This is actually a western Field gun that was made by Stevens Arms co. It is on a Browning patent, but not a Browning gun. They usually sell for $100-250 depending on condition
If you cannot easily see a serial number, then it was manufactured prior to 1968 and doesn't have one.
I don't know but I have one too with serial U116679 would like to know the age also
how old is a western field 12 gage shotgun browning patend 38535
I own a Western field 12 ga (serial no g613481) that I purchased from Montgomery Wards in 1973-4. I believe it was made by Mossberg because I have ordered a replacement stock and barrel for a Mossberg 500 that fit perfectly. Your serial no is higher, so I'm guessing it was manufactured at a later date. .
I owned a 1967 Western Field Tent trailer and the one I owned was manufactured by Ajax Mfg or Welding in Iowa. Good luck in your seatch.
The manufacture date of western field model M782 with the serial 830424 is 2012.
Stevens.
Bruin