On the drop down menu to buy stocks there isn't the option to buy the 'Music Emporium' ones, just thought I'd let you know :)

MUS and SCH were supposed to be phased out and removed from the stock market. The first step to this was to stop users from being able to buy them but to give them enough time to sell those stocks that they had already purchased in it so it wasn't a total loss for them. Unfortunately the second part of actually removing the stocks never happened XD.