Help with a Parker 20 guage

[Frank SD]

My dad passed away and his family trust simple said his assets would be split evenly to his 5 children. Among those assets is an old Parker 20 guage shotgun now sitting in storage along with some file boxes and furniture etc.

Meanwhile, my neice let it be known that she wanted to give the Parker to her fiance as a wedding gift (her fiance had previously seen the gun). That would be fine with me and my siblings if the gun is worth say $500 or so... If it's worth ten times or 100 times that, well that's another story.

I'm looking for a rough approximation of it's value. Please help.

It's a 20 guage with a serial number of 103731. Thank you.