Hello Sharp427,
Go to this link for Paula and Enzo.
http://www.cobraaccessories.com/
They sell a new part that comes disassembled and this is a good thing. You have a 535 engine and did not say what intake etc. you have on it . The tank from Finishline come with the flange, neck, tank, support all in separate pieces, the advantage here is that you look at what room you have under the hood put a cap on the tank then cut/tape it to your specific dimensions, take it to any radiator shop to have them braze the bronze together and pressure test it. You can either paint it, chrome it (I did this) or polish the bronze depending on the look you want.
Buying an existing tank either new or already assembled leaves you at risk that it will not fit under your hood with your configuration of intake, engine etc.
Good Luck,
Tony R.