The packages is called a "heatsink slug", and trade names of "Barracuda" (*), by Lumileds Corp, or "Dragon" by Osram Opto.
in the chapter on LED packaging of the somewhat-retired LED-related website Light-Emitting-Diodes-dot-org - (note different domain).
See the bottom-left image: Chapter 11: Packaging - Fig 11.5.
A possible reason for not having a clear type code for this package could be that it was not actually a LED package, but just a more generic heatsink-with-extra-plastic-lens.
*Barracuda was, at least initially, actually referring to the type of LED die itself, not the package. See [ledmuseum.candlepower.us](http://ledmuseum.candlepower.us/agilent.htm) and [Philips LED Update - page 8](http://public.ises.org/PREA/2_Presentations/3_Tech_Strat_Edu/9_Philips_LED.pdf)