For me there are two.
The first is a cap ribbon for H.M.S. AMETHYST and it must be from the period just after the WW2 in yellow thread. Sadly it shouldn't be a particularly rare tally, but the story has pushed the value up a bit and you just don't see them.
The second being a Machine Gun Corps cap badge made by LAMBOURNE. One sold on ebay a while back, but the picture wasn't clear enough to be certain that the slider was original to the badge. So I guess that it might not even exist, but that makes it even more of a "Holy Grail".
So, if anyone has the above........
Andrew