G'day mate. I'm 5'9" and a medium fits perfect for me. I'd say you would fit a medium or a large. But it depends on how you like your cockpit to feel.

 They're 2013 BoXXer RC (came stock with the bike) ...
The bars are 780.. The originals were 750.. I'm really liking the extra 30mm.. Just have to watch those trees.. haha

 It's an e thirteen ss+.. I wanted the white model but crc was out of stock so I went for black. They were on special.. from memory I think I paid just under $60au.. from what I can tell it's the same as the expensive model except the back plate is steel instead of alloy.. I couldn't see the point in paying 3 x the money for basically the same item.. it works good, it's quiet and smooth..

 Haha... Its just such a nice bike to ride..