I agree that $400 would seem more in line with what you should be paying. I just saw a brand new 23 Gen 4 on sale for $550 the other day.
If you have a local guy with an FFL, order from these guys. Here is a new 19, free shipping.
http://www.budsgunshop.com/catalog/product_info.php/cPath/21_43/products_id/714007814/GLK+19+GEN+3+9MM+4+FXS+15