Surprisingly, I've seen some reproductions of these sell on ebay UK for not that much less, mostly because they only list them once and a while to try and keep the price up. Every time one appears, it's the last one and they aren't going to do any more.

I think these were used on post '72 3000GT's in the UK as well as some RS3100's, but not entirely sure on this.
Cheers
Jamie