Springfield Armory introduced the SAR-8 as a lower price version to compete with the HK-91. Besides being slightly lower in price, the sight was modified so that it could be adjusted by hand.
While the SAR-8 is not an Oberndorf product, it is made on machinery provided by Oberndorf to the Greeks.
It's a good rifle and commands almost as much as the HK. I personally snubbed it at that time since In a world of compromise, some men don't (Old HK ad). Just kidding of course and I couldn't resist it. I didn't buy one at the time back then because I had the German HK and was completely happy with it.