[jakeru]

Sounds like a bad idea. Plastic can degrade with time, and these will also be under hot temperatures and pressure if the used engine they are off of has many running hours or miles.

Why start so many threads on the same topic?
http://986forum.com/forums/general-discussions/61351-used-reservoir-coolant-tank-question.html
Buying used reservoir tank
http://986forum.com/forums/general-discussions/61315-reservoir-coolant-leak-new-cap.html
http://986forum.com/forums/general-discussions/61305-does-anyone-bought-reservoir-tank-boxster-99-carpartswholesale.html
http://986forum.com/forums/general-discussions/61218-boxster-1999-coolant-reservoir-tank-leaking.html
Porsche Boxster 1999, reservoir coolant tank leaking