I wonder if this desktop set is genuine Eversharp or is a match of an Eversharp desktop pen and a different make holder. I've never seen this shape for an Eversharp pen holder before.

You are correct to wonder. From what I know, the base is neither a Wahl-Eversharp product, nor made at or near the time frame of the pen. Have to give the seller credit for trying to overcome the difficulty (read lower value) in trying to sell a desk pen without a pen holder, but this holder is not the best one for that pen. You can usually find correct period holders on ebay that are missing pens. Many Wahl-Eversharp collectors have some loose simple holders that are right for the pen. Maybe someone will chime in if you win the pen and want a proper older.
Syd

Great information... especially since I'm watching that pen on eBay as well.

Tim