To the Ukrainian MI6 clown child. The West has run out and yes they raided their cupboards. They do not have a manufacturing base that is sufficient for a little war, like yours.
The U.S. deconstructed the majority of its munition plants after WW2. I grew up in a small Wisconsin town that had a munitions plant. All that is left are roads, gates, a few minor buildings. Everything for actual production is gone. Then they would most likely need to rebuild the supply and infrastructure to supply such plants. Are fabulous long term deep thinking leaders... Oh wait, we don’t have those.
Not to worry sir(?), you will most likely get billions more $ for you and your faithful patrons, for such things like estates in Italy for your mom. Sure, then it’s not yours. Oh ya, hopium, you will get lots of that.
Sure, US cannot upscale production.
The U.S. plans to increase monthly production of 155 millimeter artillery shells over the coming years to 100,000 in 2025, the Pentagon's chief weapons buyer said on Friday. "We're going to be at 100,000 per month in 2025
https://www.reuters.com/business/aerospace-defense/us-aims-make-100000-artillery-shells-per-month-2025-us-official-says-2023-09-15/