PointZeroDual-Action 7cc Gravity-Feed Airbrush Set - .3mm Nozzle

Lost the spring to this - where do you get replacements?

my daughter wants to paint deer sculls. would this product be good for that?

Can it spray wood stains? Also, can I use my big air compressor provided I can dial down the flow?

What is the biggest pattern you can get with this AB?