The official source for CAP insignia and uniforms is Vanguard.
Shop with them at vanguardmil.com, (800)221-1264.
If you’re near an Air Force base, you can buy uniform garments (but not CAP insignia) at the Exchange or base thrift store.
The squadron has a “supply closet,” of used and passed down clothing items for those who are unable to afford new uniforms.
2nd Lt. Bush is in charge of this area. She can check for available clothing and help with any questions you might have.