Pistons specs question for 340 build

I called up both UEM (who make KB Hypers) and DSS Racing and was surprised I got straight onto the right tech guy in each case within 2 minutes. Both guys were really helpful and friendly and went and weighed some similar pistons. Both were within 5g of each other, at around 580 +/- 10g + 132g pin so that's interesting.

I'll probably get the DSS Piston & rings package $750 since I know they're made in the USA. I'm not sure where UEM gets the KB's made but if it's not USA I could probably guess.