I know a few tidbits...
The CA came out around 1960-62 and was produced until ca. 1966. At that time Electrolux acquired a bucket company and they decided that a commercial machine could be produced cheaper by this new company. Unfortunately, they did not have the tooling to make a square bucket (tepid attempt at humor) and new machine was born - the CB.
The CB and later models are rather nondescript and simple vacuums compared to the CA. The CA was, and still is, a deluxe commercial sweeper. It had a large, disposable bag for dry pickup with very good filtration, a large fiberglass exhaust filter, a larger version of the model G motor (think Hoover 700 vs. a 972), great suction that did not drop off as the bag filled, and it was wisper quiet.
The original hoses were 10ft. long. It came with a dry hose in the Model G pattern, and a white rubber wet pick-up hose was available at extra cost, as was the entire wet pick up kit (hose, tank insert, squeegee floor nozzle). The model G power nozzle was also an option.
Yes, Marty Rocha has a beautiful machine. They are still out there and pop up from time to time. The one on ebay is a well-used example and it looks to have rust issues, but it has the wet pick-up kit. Charles Richard knows about these machines, and Mike Rogers is very knowledgeable about them too.
There is something about the model G and the CA that still give me goosebumps when I see them...
John