Dayoptics manufactures polarzing beam combiners from two same polarizing beam and combine into one beam. The combiners including one right angle prism, one rhombic prism and a half waveplates. The interfaces of prisms and waveplates are with optical bonding. Which can withstand very high power damage threshold. Say more than 15J/cm2 @ 20ns, 20HZ @ 1064nm.
http://www.dayoptics.com/high/index-3.html
