Aloha Emery,
I would think any radiator cap rated between 13 and 16 pounds will be OK. I'm not remembering what the oem cap was rated at (CRS) & I'm at work so I can't look it up.
At least one of the vendors sells fancy radiator caps with deTomaso logos on it, but I don't know which one, see the pic below.
Your friend on the DTBB, George
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