Aerospace supplier Ducommun Inc. has reached a definitive agreement to acquire electronics maker LaBarge Inc. in a deal valued at $305 million.

The Carson aircraft components manufacturer said Monday that the acquisition of the St. Louis, Mo. company would nearly double its revenue base and bring access to new customers and markets.

LaBarge makes electronics systems and subsystems for aerospace, defense, industrial, energy and medical customers, and had revenue of $324 million last year. Its products are used in airport security equipment, military aircraft, radar systems, satellite launch vehicles, glass container fabrication and oil field tooling.

Ducommun plans to pay LaBarge shareholders $19.25 per share in cash and assume LaBarge’s outstanding debt. If approved by LaBarge shareholders and anti-trust regulators, the company expects the deal to close in the second quarter and be accretive to earnings in 2012.

“This is one of the most strategically significant moves Ducommun has ever made, one which will transform our company into a larger, stronger entity,” said Chief Executive Anthony Reardon in a statement.

Ducommun plans to combine LaBarge with its Ducommun Technologies unit, which would be renamed Ducommun LaBarge Technologies and be led by LaBarge Chief Operating Officer Randy Buschling.

Ducommun said it has fully committed debt financing for the deal from affiliates of its financial advisor, UBS Investment Bank, and by Credit Suisse.

Shares were up $1.08, or 4.5 percent, to $25.14 in midday trading on the New York Stock Exchange.