Mixmasters
Kelly,
When new, the handle and mixfinder dial would have been the same colour as the base, its only with time that the colour changes - and it has happened to every single one of these mixmasters I have ever seen. And yes it has also been seen in black too, although I do not recall it being on sale in that colour here.
We did not have the vista series here, this model (X24 I think) ran from about 1962 until the late 1960s when it seemed to disappear for five or six years. It re-emerged in the mid 1970s - the same styling (at least) as the mixer you use in your current cookie thread, although ironically in a similar colourway to the X24. These models seem to be rare, although shortly after we had the Sunbeam badged Oster Kitchen Center, so it may not have been around that long. The Mixmater popped up again in the 1990s finally in chrome and black (same styling as the 1970s version though) and stainless bowls.
For a quite period of time the models 12 (always Black/white, no pastels and no chrome) and 24 ran side by side so this 12 might be a later version. I dont recall the "hybrid" version being on sale here (Australia had some exclusive models) and indeed we do not appear to have had the model 11 either, it went straight from model 10 to 12
Al