Smith Enterprises sell only to dealers, Brownell, Midway,etc.
They are not making the sights at this time, that I know of. There production for the last several years has been doing M-14 rebuilds for the Dept. of the Navy, Marine Corp. This contract has keep them very busy.
I bought a Ladder sight from Ron at the shop two years ago. He had a used prototype in his tool box. I need one for my Winchester Legacy 26 octagon barrel 30-30.
Last year I found one for my Sons Marlin 1895 45-70. It was a Handi-Rifle type with the base that fits the rear sight base holes. This base has the dove-tail for the standard 3/8" Ladder sight. I bought the sight from a fellow that helped Ron Smith do the protype for the Handi. All I wanted was the sight and he kept the handi base. This sight has a aperature hole in the Ladder slider. My Winchester Ladder slide has a V notch.
I hope Smith starts producing the sights again, they are a quality product.