Benjamin Pump Tubes

[AmBraCol]

Hey guys, a while back I bought a used Discovery with an abused pump.  Bought it sight unseen (other than pics) and paid just over the going price for a used Discovery (down here that means it cost me more than a new one in the US...) so the pump only set me back $50 or so.  When it arrived the pump was dripping oil and I never even tried to pump with it - especially after raising the pump handle and seeing the condition of the tube.  Very heavily corroded, to say the least.  Today was the day I finally broke down and broke it down.  The brass parts all look to be in decent shape, all things considered.  The steel, however, is in need of replacement or it'll just eat up seals I'm sure.  My buddy's got an almost new pump and we've got new seals on order for it. Once they come I'll swap the old ones from his to this one and see how it goes.  Still, I'm curious - is there any source for replacement tubes for the Benjamin pump?  With the two outermost tubes replaced I'm fairly sure it'd work better and with proper maintenance should last a while longer.  There are a lot of stainless pumps on aliexpress, don't know why a US company doesn't make a stainless based pump and get rid of most of the corrosion issues.