Some Pantera parts vendors have otherwise junk halfshafts in their 'Possibles" pile. Call around- all the parts you need do is mostly keep freshly greased halfshafts from slinging excess grease around the engine compartment. I've not tried but quite a few machines from the '60s-'70s used much the same parts- TVR Griffen etc and you might get lucky on the thread size. Sometimes the cork ring is instead a felt ring.
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