Hi -

Great post!  This looks like the BullsEye Prop Balance Flange which was produced from 1987 - 1988.  There were 2 other models in this line: Prop Balance Offset and Prop Balance Old Standard.

These originally sold for $50 MSRP.  The current value of this putter will be determined by the market.  It is worth whatever someone is willing to pay for it.

These sandcasted brass Prop Balance BullsEye's featured a precisely casted cavity which positioned the head weight evenly on the toe and heel sides of the shaft to create a perfect face balanced BullsEye.  Face balance keeps the putter square during the stoke by eliminating torquing of the toe.  These models were produced only in brass finish so it looks like this has been refinished.

Thanks for your help.  I used an antique finish solution out of bottle so it will come off pretty  easy and still have it's original look.