I have done a kludge for my fixed gear bike:
Road frame, 165mm cranks, suicide hub (loctite +BB lockring + a slotted washer and a slot cut into the threads on the hub, i'm good with it), a flipped road bar and cut as a bullhorn bar.

Now the problem arises: what brake lever will it fit my bars (25.4mm, road bars) on the straight section, with road brake caliper (single pivot 7400 dura-ace)?

I know there is an option with interrupter cross levers used by their own, but it's so scarce around here, nowhere to find and shipping from eBay will triple it's value (at least). Any other option? (bar-end brake will be ok, but road bars flipped and cut does not have a straight end to fit one one of these)

I'd be ok with the yet another kludge: v-brake levers with road calipers (as this single pivot brakes have a reach of about 45mm is small reach so mechanical advantage is way greater than some long reach weinmann brakes) - but v-brake levers are for mtb flat bars that are ~22.something mm, and that does not fit over 25.4mm road bars.

Present solution for this: run brakeless but it's a risky business in Bucharest city. (way greater than NY, there traffic rules are somewhat respected, not the case here, so a brake is an urge for me)