I have upright/swept back style bars on my Hillborne and they work well for me on rides of 30 or 40 miles or on rare occasion more.
I did a 73 mile ride earlier this year on this bike to commemorate turning that age.
These bars are the Sunlite North Road bars in the alloy version. They also come in a steel version.
However I'm pretty sure you cannot fit barends on them.
I recently picked up the Nitto version of the Albatross B352 handlebar which I think is the same bar as Riv offers and vintage ratcheting Suntour bar ends that I may be trying on this or another bike in my stable soon.
Good luck with your project.
Paul in Dallas