Try this....Buy some Copper water pipe in the "appropriate" diameter.
Splice in using hose clamps and "appropriate" diameter "heater hose" from
the FLAPS.  Or just replace the rusted front rear tube with copper.

Hey, it's just plumbing, the copper doesn't know it's in a car.  And the car
doesn't care what the tubes are made of.

dangling the participle enticingly over the edge....

pensioner