Borewell low yield & pumping issues in Whitefield Bangalore, Karnataka

Need advice

I have drilled a borewell (1006 Feet) in 2015 December - I got water in two sources (2.5 inches) one at 550 Ft and the other at 750 Ft. Earlier I used to get water continuously even for 6-7 hours/day. But nowadays i am getting water continously only for 30 minutes, after that I'm not getting water. I need to wait for 1.5 hours to run the next cycle. I placed the pump at 850 feet, (4HP 40 Stage/ AQUQ TeXMO - Model RF10A/40) - so I am planning to lower the pump at 990 feet to at least get water continuously for 1 to 1.5 hours).

A local service center technician advised me to add 10 more stages on the same pump (by changing some parts on the existing pump like shaft, impeller etc) to support lowering the pump to 1000 feet (approximately 1 stage = 22 ft) Is it fine to proceed? Will 4HP support 50 stages (I saw some brands including texmo(Aqua) , Texmo(Taro) have some models with 4HP 50 Stages)

Also, as per dealer he asked to purchase a new 50 stage pump (only) that will work with existing 4HP (RF Series) motor.. but this is again a new investment.. so please adivce which one is better - option 1 or 2?