Interestingly I am reading '50 Great Curries of India' by Camellia Panjabi, she refers to the Kashmiri chillies we buy as 'so called Kashmiri chillies'. She explains; '... when I tried to trace the origin of the Kashmiri chilli in the wholesale chilli markets in India, I found that Kashmir itself did not export the quantities of Kashmiri chillies being sold everywhere, and a similar variety was being cultivated in northern Karnataka, the region east of Goa, and in Andhra, and was widely sold all over India as Kashmiri chilli!'
Apparently the true Kashmiri chilli is not as long as the ones we buy, but I don't think there is any need for concern as I doubt if any of us could tell the difference in a taste test.
By the way, if you enjoy Indian home style cooking I would highly recommend this book.
Cheers,
Ken