Dear Martin,
 
I believe the simple answer to your question is that the two forms of
Conus nobilis you mention are extremely rare.
 
Conus nobilis renatae Cailliez, 1993 was described in the magazine La
Conchiglia.  See issue #267 of April/June 1993, pp. 51-54. In the
original description of this shell, the author states that "Today, no
more than 20 specimen shells from this area (Andaman & Nicobar Is.)
recorded from this area are known in the various collections.  A study of
15 C. nobilis populations (for a total of 94 specimens) showed an
allopatric and homogeneous population exists around the Nicobar and
Andaman Islands, differing from the already known taxa".  I have never
seen this shell offered, either.
 
Conus nobilis friedae da Motta, 1991 was also described in La Conchiglia.
 See issue #258 of January/March 1991, pp.12-15. In the original
description, da Motta does not mention how many shells of this type he
was able to study.  He does mention a holotype and three paratypes.  This
form is only known from Sri Lanka (a.k.a. Ceylon).  I was once told by a
dealer that he had just sold one of these to another collector.  When I
asked how much it went for I was told $1,400.  Not cheap, so I think it
would be fair to conclude that C. nobilis shells from Sri Lanka are also
rare.
 
As Emilio has already pointed out, Rice's Prices is only a listing of
published prices asked for shells.  In general, I have had more success
getting shells originating in the Indian Ocean from European dealers and
shells normally found in the Pacific Ocean from American dealers - so I
agree that Guido Poppe might be able to help you.
 
If you get lucky and find either of these two shells, please let me know.
 I'd love to have more information on C. nobilis from unusual localities
- and the Andaman Is./Sri Lanka clearly qualify as unusual localities for
this species.
 
Warm regards,
 
Bill Fenzan
401 Sinclair St.
Norfolk, VA 23505
USA
 
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