I've taped some bar ends successfully using cheap bar tape.
As a second stage I used a length of 30~35mm black electrical heatshrink tube over the top of the padding tape. Apply heat from a hot air gun and it closed up nicely holding but not compressing the tape.
At the end, there was enough heatshrink out the front that it was unsupported and shrank so I could shove the excess into the barend with a finger. As a last step I put the bar plugs in place, and it works well.
As you can see, I had janky red foam bartape from China, cost around $2 a roll. It works fine and is thick enough for comfort, but is not very abrasion-resistant, and the red fades to pink quickly. A ~130mm length of 35mm heatshink went over the outside fine. The silver bar plugs are tamped in the end.
This one shows a flat bar that has been given the same treatment. Bartape first, then a layer of heatshrink. This photo shows how the outer end shrinks the most, and then gets tucked into the hollow end of the bars. Barplugs would make this nicer and safer.
Finally this shows another use for the heat shrink. Here's a pair of cheap nasty grips that have gone gummy or tacky. The rubber is breaking down and they should be replaced. But some 45mm heatshrink on top will conform to the outer shape and produce a nicer surface to hold.
Do note that concave features may not work as expected unless there's room for pull-down from adjacent areas. You can also buy heatshrink with a heat-activated glue lining to help, but I've never had success with that.
Heatshrink is also available in different colours, if you're feeling snazzy.
Lastly - here's some heatshrink used on the bottom of some drops. I don't currently have any bike with this at the top/stem area. This was just to retain the bartape in addition to bar plugs, not to cover it all.