By Mike Stone WASHINGTON (Reuters) – Deliveries can resume for Lockheed Martin Corp’s F-35 jet under a waiver allowing Chinese-origin alloy to go into an engine part, the Pentagon said on Saturday. In September the Pentagon stopped accepting new F-35 jets after it discovered a magnet in the stealthy fighter’s engine was made with unauthorized material from China. The waiver, signed Oct. 8 by William LaPlante, the Pentagon’s chief weapons buyer, allows an alloy in the engine’s lubricant pump that does not comply with U.S. procurement laws. Those bar unauthorized Chinese content in the jet. The …