Coolant Overflow Tank/Reservoir

j par said
Expensive little buzzard for what you get isn't it?...

IIRC it was pretty cheap. $30 maybe?

Looks like the price has increased in the three years since I bought mine. Still not a bad price IMO. Hell, a reproduction plastic windshield washer jug is $50.
Summit Racing SUM-300103 Summit Racing® Stainless Steel Overflow Tanks | Summit Racing