Longtime Pioneer collector/appreciator and restorer here. This is a GREAT thread, even if it hasn't seen any recent contributions. I've tried to contact Doc about this before as I have information that is VERY region specific and (unfortunately) VERY S/N, individual sample non-specific. I worked in the Summer of 1978 in an upscale Southern clothing concern that had a pretty big footprint in the SE U.S.. They sold the SX-x80 versions of these receivers. The company name was "Belk's". They had the equivalent of the SX-580 through the (I think but I'm not certain) SX-780. Maybe 880. (Update: It was the 880, i.e., the 890.) I don't see very much in the way of articles focusing on the Black versions of these receivers, but I can absolutely tell you that they were around and they were sold to the general public (at the retail level) in the United States. Where they were sourced from in terms of a distributor, I couldn't even begin to guess. At that time (Summer of 1978) there was a local retailer in the same Mall (Harvey's Warehouse) that sold the Silver Versions. I did not yet own one myself and spent my lunch hours comparing them in both places. One thing I remember about the Belk's display (an open quadrant of the lower floor of an anchor store, the display was right across from the management offices) was that you under NO circumstances were allowed to turn them up past getting the meters to move. That wasn't much of a problem at the "Harvey's Warehouse" shop at the other end of the Mall. The Belk's price was MUCH higher than the Harvey's price and the Harvey's price was (prohibitively) higher than the local catalog showroom dealer's (Service Merchandise and Brendle's, both now out of business) prices were. I eventually bought a silver 680 from the local Brendle's. I would've loved to have had one those beauties. Thanks for the information. These receivers are so INTERESTING. After they were cleared out, I thought I'd never see one again. I still don't see many of the Black SX-x80's on auction sites.....