I don't have one so I haven't inspected the handguards closely but I'm sure if you had the right know-how you could modify some kind of synthetic handguards to fit. They will not fit without modification though.
As for the buttstock, the only thing available right now is an adapter which allows you to install Ace stocks, so you could either put an Ace folder or Ace collapsible AR stock on it. No other AK stocks are compatible with the Yugo rear end.
