Your biggest hurdle is the fact that many bmx riders don't use front brakes. 24" BMX bikes are primarily race bikes, where front brakes are pretty much unheard of now. So finding a 24" BMX fork w/ any mounts will be hard. If you find a 24" fork w/ a hole for a caliper, you might be able to track down a conversion plate for V-Brakes.
What I would do, is this. S&M bikes has been known to do slight custom tweaks on their Frames. And their forks have an excellent reputation. I'd find my local S&M dealer, and see if they can get a 24" Pitchfork w/ v-brake mounts custom made. It'll probably cost a bit extra. If you don't have a local S&M dealer, get a hold of one of the better BMX mail-orders. I recommend Empire BMX ( empirebmx.com ). I've gotten a S&M w/ a custom paint-job through them before.
-Bill