The exact pitch and diameter have been mentioned in older threads. I think it was 26 threads per inch. the biggest problem will be duplicating the thread form. The thread form with the large radius on the roots and crests would require a custom grind. if only one or 2 taps are being made at a time it they will cost several hundred dollars to make.
Making custom screws with the standard 8-32 thread and custom heads to resemble original Krag would be an easier solution as long as you do not get them mixed up.
If I made a set for my own rifle it might take 1/2 a day. Making several hundred for someone selling them would be close to $5.00 each. So the amount mentioned in the other thread $6.00 to $8.00 dollars is very reasonable if they are hardened and nicely finished.