This is a used coolant reserve / expansion tank from a Honda 4518 / 4514. It works. It holds pressure. It comes from a running machine.

It includes the cap and bracket. The tank isn't available new, but the bracket still is it you want something without any surface rust.

The tank is yellowed but does not leak, has some grime as expected for a used part.

I have two available, both work and both are pictured and in similar condition.

TANK, RESERVE (NOT AVAILABLE)
19101-758-000

CAP, RESERVE TANK
19102-PA0-020

BRACKET, RESERVE TANK
19131-758-010