well u can actually search for yamaha kx-5 or roland's Ax 1or 7 on ebay or ishibashi.
keytars are the only breed of keyboards thats not depreciating in value nowadays.
perhaps becos its a true blue "hardware" midi controller...gear, with no patches,OS, or functions to be rendered outdated or obeselate , unlike workstations, synths and the like....hence its not prone to reali being "replaced" and deppreciated...
infact the yamaha kx-5 and roland ax-7 has doubled in re-sale value over the past 2 years...wow!!!!!!
but it seems that the roland has decided to add a nice keytar fan twist to the classic conventional midi controller keytar line by adding a synth engine to its latest Ax-synth....u can prob start buyin it online at some online stores liao....like sweetwater.