I have one. It is a modified (By Skat) OE Pump. It is where they would but a mag center pump into a stock housing. The OE Housing is cracked. I am pretty sure Glen @ Impro's could fix it by putting the insert into another OE Housing.
I'd sell it for $100 + ship as is and would include a clean OE housing to use as a core.
Glen is the one who would have originally built this.
Reach out to me at the shop if interested.
John