Pieper generally made good guns. Could be anwhere from a couple of hundred dollars to a couple of thousand depending on condition and whether or not it's a high grade gun. Go to www.doublegunshop.com and post some pics and ask about the value.
Blue Book of Gun Values can help. Most libraries have one.
Blue Book of Gun Values
An Eastern Arms model 101-7 shotgun is values at $200 to $300 in fair condition. In mint condition it is values at $450. This shotgun was sold by Sears.
There is no specific site.
I'm afraid there is not.
Blue Book of Gun Values has a description.
Seldom exceed 75-150 USD.
Try Blue Book of Gun Values.
Blue Book of Gun Values.
Blue Book of Gun Values
Blue Book of Gun Values
Blue Book of Gun Values