want to fix power steering return cooler line for last time

[gtgt__bangbang]

Want to fix my power steering cooler-to-reservoir hose for the last time, and not worry about it again.

Power steering cooler tube (the moonshiner maze) is 10 mm OD , mild steel.
Power steering reservoir inlet is 12 mm od. Mismatch. Naturally.

Originally there was a hose crimped to outlet end of cooler tube to run up to reservoir; original hose long gone but per PET looks like one of those specials; soft hose 10mm ID one end, flared to 12mm ID other side. But wait ! Theres More ! The hose is not offered as a separate item, only available with the cooler, for $$$.

Thank you Porsche for making life complicated for us loyal but Poorsche owners.

I previously had a 10mm line crimped onto cooler line, intending to try to force the other end onto the 12mm reservior stub, but with only high pressure hose (stiff stuff) available, no way will it expand that much.

At this point I am looking for a 10mm ID / 12mm(ish) OD "butt weld union" that will let me braze to cooler tube, still terminating in a compression (crimped ferrule fitting) flared tip.

The idea not unlike this wrong-size item ;