Hi Steve, i think the reason you asked this question could be because we are seeing a slow "supply" of these end pieces arrive on the market through both Chronotrader & ebay.
I believe the reason we are seeing these HLC end pieces for sale is because people are puchasing complete GF bracelets with the idea of replacing the end pieces for HLD / HLF Autavia dedicated end pieces. In essence people are sacraficing Carrera end links to facilitate placing or re-placing a GF bracelet onto an Autavia.
Its a sign of the times really , the Autavia in all its forms is going through a phase of strong popularity.

There have been some very strong periods of popularity/scarcity & price increases in the GF bracelets & their associated end links. The market seemed reasonably stable up until a period in 2009 when suddenly all the HEL double rice grain bracelets went ballistic in popularity & price. I place this down to the sudden trend of major collectors wanting all their 1st series Carrera's on bracelets. The craze spread to all the GF range and we now see clean HLF single grain Autavia bracelets trading on ebay at over $1200. The trend is unlikely to stop as it seems all collectors are are aware how scarce some of these items are. Try finding an original pair of HL end pieces for a screwback Autavia ;-(

- Darren