I think MCF itself is a Tier 1 unit, yes they do have a counter terrorist standby unit like UKSF, they call it QRS 'Quick Reaction Section'
Here are a few images
View attachment 245961 They do anti-hijack ops too, NSG is not enough because if anybody remembers the Achile Lauro incident, a hijacked cruise ship was docked in Egypt and the hostages were boarded into an aircraft, the SEAL Team Six operators having already done all the preperations, it was much easier to transport them by sea to Italy, since they were on standby in the Mediterranean. It's much more to do with logistics than with anything else, just like why the Navy has it's own fighter planes.
Yes still, NSG is the primer and only Anti-Hijack unit, apart from probably, SCTU which on one will mention because no one knows about. But NSG's domain is within the country and MARCOS have cross trained in case they are needed. Like if a situation arises where the Indian Navy is depoloyed they will send MARCOS since they are the quickest to be there. 70% of earth's surface is water.