Only ones I have seen or owned over the years came from KB. Sold it last year.
With a HV cover thats ported right & tight clearances in the motor IMO you dont need it. I just fired a fresh one Sunday with this setup & am very happy with the oil pressures. About 75 cold start & solid 30 at Hot Idle with 15-40 Rotella. Gonna drop it to 10-30 at 100 mile mark.
I know this doesnt help you find one but if you really want one you may have to find a used one? Altho, maybe you could take a wear plate & modify it to the specs of the KB? Its just a couple added grooves & some porting on the pump wear face in 1 main area I think? Thats what I remember when looking at them.
PS: I follow the Earl Brown porting method for the front cover. Do a search & you will find it pretty easily.