Looks like the going rate is $130. The last one I saw on eBay went for roughly that amount, maybe a bit more. Christian at
OK Parts in Germany is reputable, as is
Rainer Hurtienne . These two may be your best source, that is if AFRA in Milano doesn't have it.
Matt at
Re-Originals in the US has them as well.
Hope this helps,
Mike
'58 Spider Veloce
'59 Sprint