A Western intelligence report cited by Bloomberg claims that Iran is producing about 50 ballistic missiles a month — roughly half of its pre-war capacity — and may have "at least" 1,700 ballistic missiles in its arsenal.
Israel estimated that Iran had about 2,500 ballistic missiles in its arsenal before February 28, and Iran had launched at least 2,200 of them during the war, suggesting that Iran had built up to 1,400 new missiles since then (or the Israeli estimate was not).
The report also says Iran has "thousands" of Shahad-type weapons, of which at least 4,900 were fired during the war.