This doesn't work as you hope it does. The Buy phase is split into two halves - first you play your Treasures, then you buy things. By the time you get around to buying this Event, it's too late to play any of the treasures you drew, and very little else you could draw would be relevant (corner cases like Trader aside). How about a reveal+play? It's wordier, but it at least works within the rules.
Maybe I'm just stupid, but the first time I read the card, I assumed that both the flipping
and the draw were dependent on trashing, so if you didn't trash, nothing at all happened. Later re-reading makes me think that you wanted the draw to happen regardless of whether the player trashed anything. If that's the case, it would probably need rewording for clarity, or just have a separate rules section explaining how it works to prevent idiots like me getting confused.
If both flipping and draw
are supposed to be dependent on trash, then there's no real need for the "may":
