This is a quick search on eBay, where I found mind. if you have a Chevy, they have them with the proper badges, but nothing technical correct for GMC, so I found a generic one with no badging. The make a few styles, you need to look for a "swing out" type, they make a pull out type but it would mount to the underside of our dashes.
http://www.ebay.com/itm/VINTAGE-ORIG...VZKkNb&vxp=mtr
http://www.ebay.com/itm/Vintage-Klee...FY2s-n&vxp=mtr
https://www.ebay.com/sch/i.html?_odk...enser&_sacat=0
Use this search string terms "vintage 195* tissue dispenser"