Well, they actually depleted their stocks with this war, so they could spend trillions just restocking, for years.
It's not going to be sufficient, tho. The economy is too sluggish and exhausted. Nobody wants to take on credit, just to build things they can't sell, and they don't have the workers to build it all, anyway, and the customers are dying off.
But Rheinmetall shares are a good bet, at least.