What are you alluding to? The Constitution of the United States? The New York State Constitution? A local municipal code What?
If it is the US Constitution, I don't see where it applies at all.
"No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal; coin Money; emit Bills of Credit; make any Thing but gold and silver Coin a Tender in Payment of Debts; pass any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or grant any Title of Nobility."
They wouldn't be entering a treaty or alliance or confederation by purchasing weapons from a foreign source. In fact, I believe Sig Sauer, and Glock are two major suppliers of handguns that are both foreign.
They also wouldn't be granting Letters of Marque and Reprisal, coining Money, or emitting Bills of Credit, passing any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or granting any Title of Nobility. Unless it is your position that they have to pay for the weapons with gold or silver coins, I really don't see what applies here.
That isn't all of Section. 10. but do keep trying.
OK, here is the rest:
"No State shall, without the Consent of the Congress, lay any Imposts or Duties on Imports or Exports, except what may be absolutely necessary for executing it's inspection Laws: and the net Produce of all Duties and Imposts, laid by any State on Imports or Exports, shall be for the Use of the Treasury of the United States; and all such Laws shall be subject to the Revision and Controul of the Congress."
"No State shall, without the Consent of Congress, lay any duty of Tonnage, keep Troops, or Ships of War in time of Peace, enter into any Agreement or Compact with another State, or with a foreign Power, or engage in War, unless actually invaded, or in such imminent Danger as will not admit of delay."
2nd paragraph deals with duties and imports. Nothing applies there.
3rd paragraph, more about duties, no troops or ships of war in time of peace, agreements or compacts with other States or foreign powers, engaging in war unless invaded... Still not seeing anything preventing a State from purchasing weapons from any supplier that suits its needs, so long as they are complying with federal import laws.