You can get baluns that have RJ45 jacks and split out to BNC and pigtails... but I just do it like this:
Heavier by a whisker 23 AWG vs 24), but not necessary. Considering these cameras can be happily powered at 12V over a single 24AWG pair, which is pretty much the lowest you can go... yeah, not needed. Certainly not worth the added expense.
Sorry for the noob questions, but after looking at your photos why not just use this: http://www.easterncctv.com/accessories/ev01p-vp-t.htm
Only reason I ask is because I'm going the balun route too and just doing research.
EDIT: I should mention I plan on using a EV08P-VPS