Buy one (1 on sale)
1983 (Dec.)
Initially sold for ¥64,800
The Yamaha YIS 503 is a stripped down CX5M aimed at the home computer market. It comes in silver, retains the "YIS" name Yamaha once envisioned for its ecosystem built around the PU1 and doesn't have any SFG module preinstalled.
It's unclear whether at this stage Yamaha was still selling the original YIS line or the advent of MSX computers wiped away any previous model.