RHD steering racks are all but impossible to come by. You would also have to cut a dash and re-fiberglass etc. all in all not an easy task and one you'd want done by a competent shop.
If a conversion is your preferred route and you find a Pantera here in the USA you might consider talking to the vendors to see who can do the conversion this side of the pond prior to shipping. They at least have Pantera knowledge and parts readily available.
When I lived in Australia I had a Corvette that had been converted to RHD, whilst looking for that car I saw some real dodgy looking conversions.
Julian
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