Even if the US and EU pony up the not insignificant amount of cash to do it, there's still nothing that can put 1000t into orbit, let alone L1. And splitting it up into 100t segments isn't a solution, since L1 is unstable. The segments will need power, thrusters, gyros, propellant and guidance for station-keeping, so there goes a large chunk of your mass budget. To compensate for that, you need more mirrors. And they need to be continuously replaced as they break down or run out of propellant.
Even if the US and EU pony up the not insignificant amount of cash to do it, there's still nothing that can put 1000t into orbit, let alone L1. And splitting it up into 100t segments isn't a solution, since L1 is unstable. The segments will need power, thrusters, gyros, propellant and guidance for station-keeping, so there goes a large chunk of your mass budget. To compensate for that, you need more mirrors. And they need to be continuously replaced as they break down or run out of propellant.