Well, I fully expected the bidding to be far more aggressive on this Kirby than it proved to be. This is one of the "R" - "Retail" series of pre-500-series Kirbys sold in retail stores. The on-off switch is in the handle; the cord goes from the motor up through the handle. There were four R models - R, 1R, 2R, 3R and 4R, corresponding to the four C models (C, 1C, 2C, 3C and 4C) sold door to door.
I am not sure of the exact dates of the four R and C models; I just know that the Models C and R came out in 1935 and the 2C and 2R in 1939.
When the first 500-series model came out, the 505 in 1945, Kirbys were no longer sold in stores but exclusively by home demonstration.
Thus, the four R models -- being the only Kirbys ever sold in retail stores -- are quite rare. Even besides their early date of manufacture.