When I was a kid I used to make a bunch of lego stuff and throw them off a balcony to see what survived, I also liked trying to make parachutes to slow the fall but they never worked too well. So I made a mock-up for a lego parachute block, pretty simple kinda fun.
Is the parachute going to be plastic? or will it use a different material to be more effective?
I suggest trying to add a lid piece to make it appear to be a regular Lego until it is opened into a parachute.
Is the parachute going to be printed as well? How are you going to make this piece fit with other legos?
Depending on what material you use to print this, I would suggest adding a coating of some kind to the parachute to make is shine like the model does.
An idea you could use might be to add the top of a lego onto the top of the parachute, or slightly suspended above it with supports. This would give the effect that the parachute had just launched out of the Lego and that the piece is actually in motion.