I have no specialist knowledge but I do have considerable experience re boreholes and ponds in Isaan.
We had a bore drilled earlier this year. The guy charged 15,000 baht for the first 45 metres then 500 baht for each additional metre for a 4 inch bore. This is quite cheap. A lot of guys charge twice that amount...., and more.
A 6 inch bore would have cost 50,000 baht for 45 metres.
The pump and ancillary items cost a further 10,000 baht or so, including labour.
Drilling the bore took 4 or 5 hours, fitting the pump took another hour or so but not on the same day. Apparently it is best to allow the bore to settle before fitting the pump. I don't know exactly why.
We had the same guy (family actually) fit the pump as drilled the bore. This was to avoid any possible merry-go-round of blame if one or the other didn't work properly.
A borehole will work well for up to 10 years. When they're beyond their best they start dragging up lots of grit and dirt which will damage your pump, silt up your taps, deposit copious amounts of grit in your shower tray, etc. You can have the bore cleaned but in my view it's best to write it off and have a new one drilled. Cleaning and drilling a new hole cost about the same price - cleaning is usually only re-drilling anyway in my experience.
The diameter of the borehole, the distance from ground level to the water surface, and the type of pump used will determine the yield. The depth of the bore is only critical if the water is a long way below ground level.
Our old bore was 2 inch and 42 metres deep - most of our neighbours' bores were double that depth. Our old bore with a Lucky pump consistently pumped 6 or 7 litres a minute - more than enough enough for domestic use and some plant watering, but pond-filling took ages but was still doable. Most of our neighbours used cheaper pumps and their bores often didn't yield at all.
Our new 4 inch bore can fill a 7,000 litre pond in just a few hours so my guess is that it pumps at 20 or so litres a minute (that is only a guess) and might work faster if we pumped through open ended pipes without taps - but I am only guessing here.
in my experience nobody will make any guarantees about how much water you will b able to pump.
I hope that the above is helpful.
I will be happy to answer any further questions.