Looking for 408 lower ball joints. Part No. 407-1-23169 or an equivalent

[dwomby]

These seem out of stock wherever I have asked so far. I would like to buy two new, NOS or very good condition used. They may be unique to Bristol but I am hoping the same parts may have been used on other brands. We know the Jaguar XJS upper ball joint can be used in our cars and I have found some parts from Austin Healey and MG are identical to parts in my 408's front end but, so far, can't find anything that looks like these ball joints. Any thoughts or ideas on a source, please?

David