For some reason, FN restricts this ammo. That being said, you are able to find it sometimes on Gunbroker or even on this forum in the For Sale section (Market Place Forum). But due to the restrictions, you are going to pay a premium for it no matter where you get it from.If there is a wanted section of this forum please forgive this post. I am looking for availability of sub sonic 5.7 ammo for my new ps90 sbr. I have no idea where to look for it and what the prices should be if it's available. Thanks in advance.