They always say you'll find what you're looking for when you're not looking! I was out and about with my wife at Wal-Mart and Target, and ended up finding a few headsets with answer/end buttons that work with the 7135...

At Wal-Mart, I found the Belkin E Series OverEar Boom Headset (F8V920-EHB). For some reason, I can't find a link to it on the Belkin website, but I'm using it right now and it's a great headset for $12.97! It has the answer/end button and a volume control. It says the answer/end button is for compatible Samsung phones, but it works well with the 7135!

At Target, I found the GE/Sanyo "Platinum Power" Over-the-Ear w/ Answer button and Volume control. There was no model or stock number on the package, only an order # on the back of 40764. The package shows compatible with Samsung, TouchPoint/LG, and AudioVox, but I tried it and it works with the 7135. It was $19.99. There was also a GE/Sanyo "Platinum Power" EarBud with Answer button and telescoping microphone. Again, no model or stock number, but the order # on the package was 40768. Same compatibility as the Over-the-Ear, and it was $14.99.

I updated the list in the first post of this thread with these 3 headsets.