options to hush the Texan

It was said when Air Force first introduced the LSS they where going to make it available for the original Texan but I don't know if that was ever done or not.

Neil Clague on mine.

I also use a Neil Clague moderator on my .257 Texan. https://youtu.be/ZDnQDMAFgyI

So, is the Neil Clague quieter than the Hunters Supply air stripper shroud?

By far. Was with my friend Kevin on Friday and he shot his .308 Texan with Hunter’s supply moderator and I shot my .257 Texan with Clague moderator and the sound level difference is substantial. I also think the overall balance of the Clague is better. We hiked all over the place and a Texan is a beast to carry. 

Yes - they are custom made to fit your barrel - look and perform better than Hunter's supply version. http://petersoncorner.com/clague/gallery.htm