These bulbs are branded as Mysore Palace, which is the place they are located (it's a real place and a famous one). The branding shows that these are special. These do not relate to the  'Mysore Lamps' brand or the 'Mysore' brand and are specially ordered lamps which have been rebranded. Unfortunately, they cannot be bought generally, and cannot be taken at any chance, even if it's filament is broken.
They are rated at 15w, 250v with E27 holders. Their lifespan is unknown but suspected to be a lot longer than normal since they get turned on quite frequently and it would be very hard to replace 10,000s of them (yes there's really that many).
Does anybody know more?

cool place and claims to ge the ONLY lit royal palace in India
gotta think they go through 50K bulbs a year / they must show up somewhere you would think
also don't think they are special "long life" IF that is true as it is lit up for 45 minutes every sunday + holidays and longer for a event "Dasara" (sorry dont know what it is)
it has 4 SUB STATIONS to power it!
https://timesofindia.indiatimes.com/city/mysuru/a-lakh-lamps-light-up-mysore-palace/articleshow/16885422.cms
https://youtu.be/ehKHtXzZxFk?si=V8Xl3wCTkd1m0bXW a video of it lighting up
(all from GOOGLE search) - personally never gone there

When I went there, I saw many MV, HPS and SON-E lamps. Many on the inside were dayburning while the outer ones only light along with the incandescents. The deluxe white, warm white and the deep orange make a deep 2000k-ish ambiance. There were also 2700k and 6500k leds inside but only for smaller rooms.
The 'Dasara' festival lasts for about 10 days (9 nights) so the incandescents would be lighted up for the 9 nights.
I also saw that the bulbs were never missing, or half damaged, only fully intact or only the base of it (glass completely gone). This is surprising considering that many bulbs are reachable to the public, even little kids could play with them.

the video I saw on the light up looked like there were some MV lamps around the centre part of the archway entrance

The entrance does have MVs, the higher areas have SON-Es with warm white colour and the long hall areas have HPSV lamps. Some of the inside hallways also have MVs, but many are very dim and greenish.

Update- I actually got one ! Looks like when group replacements happen, you can take the decommissioned ones!
Lit up - https://www.lighting-gallery.net/gallery/displayimage.php?album=lastup&cat=-8023&pos=2&pid=242396

wow cool score
did they hand it out or was it more of a "fight" to get it?

Special permission