http://www.amazon.com/Lebert-Fitness-Equalizer-Yellow/dp/B001LOO8UW/ref=sr_1_2?ie=UTF8&qid=1424844898&sr=8-2&keywords=dip+bars

Looks like these, but I doubt you'd need to spend $100 to find or make something similar.

edit: http://www.amazon.com/Apollo-Athletics-High-Parallette-Bars/dp/B00N11OTMK/ref=sr_1_32?ie=UTF8&qid=1424845052&sr=8-32&keywords=Parallettes

More likely these, but they are more expensive. Probably worth it if you're near that level.

Edit2: Better yet, make them yourself with PVC from homedepot.