Arne Vodder for H. P. Hansen's Rosewood Desk circa 1965  

The things that throw me off are the drawer pulls,:wings: and jointery. 
 
 Palle Dinesen would know best. 

It's been a while since I've posted. After digging a little deeper, I belief Leif is onto something. Svend Madsen designed several desks for H.P. Hansen's. I found a similar desk designed by him, circa 1950's, where the legs and how they support the cabinet frame are very similar in design.
Locally, I found an antique repair shop that may have a replacement filing cabinet drawer guide. Let's hope I get lucky. Otherwise, I'll create a solid model of the part I have, and have a 3D printed piece made. That's better than nothing.

Finally, after several months I'm satisfied with the H.P. Hansen desk repair. With a LOT of difficulty, I was able to remove most of the sag, due to warping, from the top. The slight sag created a gap where the desk top mounts to the cabinet frame at the outer edges.
All the drawer fronts and the desk top were refinished to bring back the original color and luster; a perfect match to the color and luster of the remainder of the desk!
I found a replacement drawer guide from Rockler Woodworking Supply and used the drawer glides that came with the drawer guide. It all fit perfectly. Thank you for the lead, Leif.
I added a picture of the finished piece. What impressed me, from viewing from the side of the desk, was how the manufacturer matched the rosewood veneer grain carried up the cabinet side panel, across the desk top, and down the other cabinet side. I'll add an image of this later.