As a non-licensed/exempt person, you can not legally acquire an aftermarket auto-switch for a Glock in the USA or in the EU.
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"If someone has a gun and is trying to kill you, it would be reasonable to shoot back with your own gun.” - Dalai Lama (Seattle Times, 05-15-2001).
Well you can acquire anything with enough money. But it's a painful wager I wouldn't want to loose.....considering if you were caught you'd find yourself in possession of a one way ticket to federal pound me in the A prison.