On the TKS system there are many standard parts which we have to obtain. I initially sent the list to LAS who could not be bothered to even look at it, so we bought most of them from Adams and Saywell.
Three of them don’t reference to anything, not clearly or not at all.
NAS 686A-06 anchor nut
BSA206-B12 screw
5.632.0.40.065 rivet
For the first I see some potentials – it looks like a riveted nutplate.
I have asked CAV but they don’t seem to know! The whole system was developed about 20-30 years ago and the internet goes back only about 15 years 
The usual aircraft parts distributors don’t recognise them either.
Many thanks for any pointers.
NAS686 is deprecated since ‘71.
Replaced my NASM21059 and 21060 (sometimes listed as MS21059)
I’ll add the datasheets tonight
I think the first one is NUT FLOATING ANCHOR MS21059L06 but the others I can’t find. The first two appear here
The “rivet” appears here, item 136. It could be a pop rivet
The screw appears to be B206-B12; a 6-32 countersunk screw, 3/8" long. As always, superior quality (stainless steel) items are on Ebay.
The 3rd item, 136, the rivet, is a piece of trivia for attaching relocate luggage compartment tiedown clips.
UNC A2 Stainless Steel Countersunk Pozi Head I
Actually, aviation hardware is typically Phillips rather than Pozidriv, although bigger guys like Airbus use Torq-set:
