The Repops have Pro Neck laser etched in them. This is the most important way to tell. The updated picture I took at an angle shows the grain strands in the material. They cant do this with the repops as the repops is a different type of material than the originals. I also have a blue one listed.
If anyone has any questions let me know. The item "Old School NOS Pro Neck Gold BMX Stem Triton PK DG JMC Tuff Brute Redline" is in sale since Monday, January 11, 2021. This item is in the category "Sporting Goods\Cycling\Vintage Cycling\Vintage Bicycle Parts". The seller is "rossus_0" and is located in Presto, Pennsylvania. This item can be shipped worldwide.