It existed... for a brief time. Circa 2008 Roland offered the E-50 and E-60 which were based on the G-70 operating system. They lacked some features, including the sliders, but they were very approachable MOTL arrangers with most of Roland's feature set and touch screen. As I slowly acclimate to the BK-9 I'm hanging onto my E-50, IMO it still does some things better than the BK-9!

If you really want to buy one, set up a search on eBay.uk. Roland's marketing and customer support in the USA has been TERRIBLE. But I suspect they sold more of these in the U.K. / Europe, so you're more likely to find one on the resale market there.