Talos (1955), Bomarc (1958), ASMP (1986), Bloodhound (1958), Sea Dart in (1973)...so saying that we're the most experienced would be bit of an overstretch. Contractors have mastered ramjet propulsion and cruise missile technology decades before us, it's just that they didn't try to compete in this niche before 2005. They were more concerned with developing counters for supersonic cruise missile as it was an adversarial threat.
As for price; yes, we can theoretically produce things cheaper than others. But there are numerous other things that goes in pricing decision than just the availability of cheap labour; take the price of BrahMos itself for example. From economies of scale to how much margin one can reduce, n number of factors. One of the biggest factor of pricing is the availability of cheaper dual use items that come from non defence sectors. Let's say you've conceptualized a new missile that because of its clever design manages to reduce cost but as soon you'll starts placing orders with other local firms for items like screws, actuators, drivers, CNC service, sensors...you'd realise how exorbitantly high they charge. But you're in defence so like automobile or consumer you don't have the luxury to import these from China.