After reading comments on various forums from people claiming these work with the HD131xe. After ignoring the item description about compatibility, I thought I'd give them a try as they were fairly cheap. To be honest I didn't think they would work and hoped for the best, switched to Sky 3D and turned the projector to SBS mode and then turned on the glasses. The image flickered and hurt my eyes but all I needed to do was press the button on the side of the glasses to switch the L/R mode. The projector was set to DLP Link Mode automatically and the glasses just worked out of the box.
Now I know they work, I will definitely be buying more glasses.