On the subject of Indian pens, here’s a list of those I found. There may be others.
Airmail/Wality, Guider*, Deccan, Kim & Co, Ratnamson, Ranga*, Varuna, Camlin*, Serwex*, Fellowship*, FPR*, Gem & Co.*, Asa Pens (Gama)*, Oliver*, Abhay Pens, Camay, Lazor*, Hamraj* and Gala.
Edited to add Fosfor Handcrafted Pens
Not all are available online but those that I have marked with an asterisk are at time of writing. I didn’t search terribly hard so it may be that some of the others are available too.
I would be interested to hear of your experience with Indian pens, good or bad.
Goodwriterspens's Blog 
hello Deb – Like a lot of folk I tend to be unadventurous and stick to names and pens that I know – the sort of things about which I can find some info in my books – the result of which is that almost certainly I don’t have anything made in India.
Having said that I have a couple, which I acquired at the same time, and which for all I know, might be from that area. The construction lacks quality, although doubtless they would perform reasonably well as a f.p.
These are P. 51 look-a-likes, with gold coloured hooded nibs, an arrow clip and ring clutch that locates into some internal part of a chrome coloured cap. The feeds have longitudinal combs, and the section is flat sided on the top half. Section and barrel are plastic in a deep maroon.
Nothing on the cap, but the barrel imprint reads ‘SEA EAGLE – BEST FOUNTAIN PEN’, and the pressure bar inside the aerometric filler case reads ‘SPECIAL MADE – BEST IN THE WORLD’.
MIght anyone know the origin of these, please.
I had a search, Paul, but no luck. That one remains a mystery, I’m afraid.
You should also add Fosfor Pens, fosforpens.com – excellent handmade pens. I have a reasonable collection of Indian pens and they’ve really improved in recent years, as the nibs, which were always the weak point, have been improved (lots of manufacturers now offer Schmidt and Jowo nib and converter options). There are also some new ebonites coming out which offer more choice than the old ‘traffic lights’ (brown mottled, green mottled and black) and quite a lot of nice acrylics too.
I’ve dealt with Fosfor, Ranga and ASA personally and found in all three cases that they’re very open to experimenting with their customers if you want, say, a slightly different section profile or to provide your own blanks, and very open to feedback as well. All three of these manufacturers are online and easy to deal with by email.
Thanks for the information, Andrea. I’ve updated the post. Lovely pens!