Pentax usually made celebration packages of current cameras.
Like :
LX Gold (1981)
Special edition, celebrating 10 million SLR manufactured by Asahi Opt. Co.
Super A European Camera of The Year (1983)
Special package variation of the Super A, including a gold seal, a special logo strap, an AF200T flash and a special presentation box. The SMC Pentax-A 50mm f/1.7 lens also featured a special front cap with "EUROPEAN CAMERA OF THE YEAR" gold lettering This special edition camera was made on occasion of getting this 1983 award.
K1000 Anniversary (1994)
Special Edition of the K1000, including SMC Pentax-A 2/50mm lens, made on occasion of 35th anniversary of Pentax-API partnership. 300 pcs made for Italian market only.
Z-1 Special Edition (1994)
Special Edition of the Z-1, including SMC Pentax-FA* 2.8/28-70 zoom lens, made on occasion of Asahi's 75th anniversary. Available worldwide.
LX Titan (1994)
Limited edition of the LX for the Japanese home market only, made on occasion of Asahi's 75th anniversary. Natural titanium housings and special strap and presentation box. Only 1,000 pcs made.
LX Limited (1996)
Limited edition of the LX for the Japanese home market only. Black lacquered titanium housings and special strap and presentation box. Only 300 pcs made.
MZ-3 SE (1998)
Special Edition package of the MZ-3, including the SMC Pentax-FA 43mm f/1.9 Limited, UV filter and brown leather strap. Only 2,000pcs made for the Japanese home market only.
LX2000 (2000)
Limited edition of the LX for the Japanese home market only. Equipped with a SMC Pentax-A f/1.2 50mm Special lens. Only 1,000 pcs made.
MZ-3 Limited Package (2000)
Limited package of the black finished MZ-3, including the SMC Pentax-FA 43mm f/1.9 Limited in black finish, UV filter and brown leather strap.
Introduced Nov. 25th, 2000 for the Japanese home market only.
(I have no idea, what something like this would go for used. I think it would be extremely difficult to find)
Bayonet Oddities
And then there was the
Prototype 50th anniversary of the Asahi Pentax (AP) camera
heavily based on the K10D (except for the lack of a built-in flash),
(The prototype was just for celebrating the 50th anniversary, and Pentax did not release a body, not even in a small batch).
The K10 Grand Prix edition
courtesy Frank
Hands-on with the two DA* zoom lenses :D [Page 1]: Pentax SLR Talk Forum: Digital Photography Review
And then there was the
special edition White K-m, which sold out almost entirely on a pre-order basis. It seems people have fun with these side track products. (If I had a teenage daughter, I would probably get her a white K-m).
Bodies don't last forever, might as well have some fun. The white K-m got Pentax a lot of free publicity, on Pentax own terms, trying a new direction. (Just like the stroke of genius of Ned getting free airtime, with a backup Leica
)
For a 90 years special celebration package, I would hope for a Special Edition K-m. Inspired by the LX Limited, it could be black lacquered titanium housings, sealed and then with Samsung sensor. I would for sure try and order one of those. (Maybe drop the built-in flash, for a better ViewFinder)