LaBarge Inc. (AMEX: LB) shares rose 9.1% to $19.02 a piece, on volume of 1.9 million shares, dwarfing a daily average of less than 35,000. This, after Ducommun Inc. (NYSE: DCO) said it would buy the electronic manufacturing-services company for $19.25 a share. Ducommun shares improved 3.9% to $25.00.

Sirius XM Radio Inc. (Nasdaq: SIRI) saw 25.9 million of its shares change hands, trailing its daily average of 54 million. Prices inched up 2.7% to $1.70, after announcing today it would provide live radio coverage of this week’s Masters Golf Tournament from Augusta, Ga.

General Dynamics Corp. (NYSE: GD) shares fell 5.7% to $73.00, on volume of 9.7 million shares, far surpassing its daily average of 1.9 million. This, after a unit of the defense contractor said four employees died Saturday when an aircraft crashed during a test flight.