Check out the add-a-overdrive set-up on Craigslist. He advertises it as an early Gear-Vendors but it's not a Gear Vendors brand. Not sure if it's a Hone-O-drive, a US gear overdrive or some other brand. Gear Vendors has always been electrically shifted & Laycock designs were electrically shifted from back in the early 70's.

http://dallas.craigslist.org/ndf/pts/4843691696.html

I don't know the brand but a long time ago I saw a baldwin motion car in Hotrod or CarCraft. It had a manually operated overdrive. while the one you showed looks similar to cable operated fresh air vent, the motion car had a long lever on the passenger side of the tranny hump but hey a cable is a cable right? If I recall correctly it was a Hone o drive or however it's spelled. No shift on the fly though.

I had a 64 Rambler with a three-speed on the floor and a second stick that was the overdrive called a twin-stick I believe.

the "twin stick was also available in the late 70's early 80's in the Plymouth c\Champs and Dodge colts And then there is the
https://www.youtube.com/watch?v=MXW0bx_Ooq4
Stolen form another recent posting, LOL

That's not a Gear Vendors at all. Gear Vendors basically bought-out Laycock-DeNormanville back in the late 70's. Their units are easily identifiable by the ribbed aluminum oil pan on the bottom and the large electric solenoid on the side. So, this one operating by cable automatically precludes it from being a GV/LdN type as all of those were electric. Gear Vendors/LdN units are also reasonably compact and much stubbier than this.

This might be a Hone-O-Drive. H-o-D could be either cable or lever actuated.

Much too modern to be a Columbia, and also I'm pretty sure Columbia's attached to the differential, not the transmission.

Here's a pic of a Hone-O-Drive unit.