I am not sure if the one you show would slide around or not. That's the thing to look out for.
I got a Rider's Choice brand new on Ebay
for $130 and I LOVE it! It's as good as my saddle but has that close contact and doesn't get my butt dirty!
While researching bareback pads I had a lot of people recommend the Best Friend pad. That too can be bought on Ebay and a few horse catalogs. I've never heard anyone complain about them and they are about $69 I think. They come in both english and western.