https://www.ebay.com/sch/i.html?_nkw=Accuform+Signs+Portable+Rail+Clamp+Sign+Holder&_sacat=0&_dmd=2

Accuform Signs Portable Rail Clamp Sign Holder

$135.00
$86.00

Portable Rail Clamp Sign Holder, Galvanized Steel, Height 47 In, Width 14 In, Gray