Some mfg economics that'll help understand defence platform prices. In terms of per unit cost 

1. mfg 100 platforms in one assembly line over 5 years is cheaper than on 2 lines in 2.5 years. 

2. mfg 100 platforms in one line is costlier than 200 platforms in one line.

So if services as end customers seek competition in fighter mfg (never heard of it ever in any country of worth), they better pay up for the jacked up costs that come with preparing a mfg line only for 20 aircraft for each of the maker and also for the training of 3 times the workers and supply chain. @acorn 
While what we saw was the MoD negotiating with its own mfg agency HAL to reduce prices from Rs 45000 crore to 37000 crore sans post sales service. 

At our L1 prices, seeking competition is a premium. End of the day, whether it is HAL or Tata or L&T or any pvt player, they all would've faced the same engine supply issues from GE. So, little that a pvt player could've done.