Just to be pedantic, they are not actually L1A1's. They are actually called IA's.
The Indian government also has a large number of genuine L1A1's purchased from the British and Australians. (MARSTAR has a couple of these former Indain L1A1's for sale). They also purchased some FN FALs from FN, and wanted to produce them themselves, but didn't like FN's high royalties per weapon and the offsets FN insisted on (i.e. buy our machinery and technology package, hire some of our engineers etc).
As a result, the Indians reverse engineered a set of drawings using both the L1A1's and FN FALs in hand. Production started in 1963 at RFI (Rifle Factory Ishapore). They never did get any kind of license or agreement with FN, so it is technically an illegal copy.
Because of this, while the rifle looks like an L1A1, it has both metric and "inch" features. This makes it unique, but since it is closer to the "inch" patern, there are lots of them out there with Canadian wood and topcovers, because they were cheap at the time (still are relatively speaking), and C1A1's were rare.