Brahmos's range is not greater than what is being mentioned in open source. The size and weight does not allow for greater range anyway. MTCR does not allow ranges of greater than 300Km, nor can it be modified for extended range in house.
The only way to extend the range is by making a whole new missile. According to one such rumour, a new supersonic long range LACM will be made. But of course these are only rumours. A 1000-1500Km range Ramjet or Scramjet will be too big and too heavy for today's technology.
Shaurya has nothing to do with Brahmos. Shaurya is a quasi ballistic missile which does not follow a ballistic trajectory. Other than that it has multiple stages and uses solid rocket motors and is meant to replace Agni I while achieving greater flexibility against enemy ABM systems. Bhramos is a different beast altogether meant for entirely different purposes.
Brahmos and Shaurya have nothing to do with each other since they were both developed by different teams.