Here are some pictures of a similar model
<span style="font-family: tahoma, arial, helvetica, sans-serif;">What I found were two references to what appears to be the same model (#RDA-3). One is a Crisco sweepstakes contest, which gave away 1,200 Westinghouse upright cleaners (!). This contest ad was dated April, 1938, and appeared in the Better Homes and Gardens magazine. </span>
<span style="font-family: tahoma, arial, helvetica, sans-serif;">The second item is an article that appeared in The American Home magazine, dated May, 1939. I believe these are both the same model vacuums. A few interesting variations: This model looks like it has a side-clipped bag; the bag stretches across the front of the machine, tucked behind the motor housing. The bag has a clip in the lower right-hand corner of the bag that clips to the motor housing to hold the bag in place as it inflates; this feature appeared on some Eureka models, also, and on some Westinghouse models, especially in the 40's. I'm not sure if you can see this in the Crisco sweepstakes ad. Your cleaner, which apparently has a catalog number of RS-3, may have been a variation of this model RDA-3.</span>
<span style="font-family: tahoma, arial, helvetica, sans-serif;">Here's the first, the Crisco ad: </span>
