Thanks for your brevity JS but can't say I feel any kind of satisfaction or clarity from your response. Not that that's what you had in mind.
Not sure how you'd know what I had in mind. I was just trying to clearly answer your very specific theoretical question.
However, suspecting from your subsequent post that you're actually looking for details on the mechanics and/or source for such a pump...
Any size or power of turbine and pump could be set up to work, as long as it can sustain adequate pressure while pumping. It's just a matter of how long it'll take to inflate your balloon. I doubt you'll find a contraption already set up for your task, at least on a small scale, so you'll probably have to improvise:
1. Find any 'cup' or alternate type of turbine that you can attach a pully or gear to. Almost any size will do.
2. Find any functional piston or diaphragm type air pump. Impeller type pumps may not work because of stalling flow at slow speeds and (even slightly) elevated pressure.
3. Connect the turbine and pump with pulleys or gears, and experient with ratios to make the pump run as fast as possible without stalling against the expected inflation pressure, in the ambient wind speed.
A bigger, more powerful turbine will allow you to run a bigger pump and/or at higher speed, inflating your balloon faster, but it's not necessary. Even a miniature 'cup' turbine, connected with the correct precision gears to a tiny pump, will get the job done, albeit slowly. You'll only have a problem if your turbine is so small it can't even overcome gear friction at a ratio adequate to turn the pump, or if your balloon is porous, in which case 'slowly' might not overcome leakage.
There are way too many variables you haven't provided for anyone to specify all of the parts and ratios required, so you'll have to experiment. I suspected you realized that, so I originally replied with the intention of simplifying what could otherwise appear a complex question, like those trick school test questions which throw a lot of irrelevant parameters at you.
Once inflated, if your balloon is (practically) nonporous you won't need the pump to keep it inflated. Just clamp the nozzle and forget about the pump.