Please be aware that the “First cost estimation” of 762.75 THB does not based on the same information of the other 2 cost calculations.
Meaning the first cost estimation, it did not have the correct number of stones and surface area for plating.
So at the moment, we are getting a new cost calculation for the chain link option, and the product engineer (Khun Eiad) will update you again.
But also for your information, Khun Sod have already aligned the execution with Julian in 3D, and they both agreed with the pinched prong execution.