I have never heard of this for the TR. You will probably have to have a metal shop fabricate the part for you. Also in the UK (where I believe you are) is Hill Engineering who does metal parts for Ferrari. Call him, perhaps it will be a new part he would like to make for others too.
1-5 Mercy Terrace
Tel: 020 8690 2163
Please tell them I referred you (Andrew of Ferrari Forum). I think they will be your best bet. They do lots of custom work.
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