Loose balls means any old axle
will work... once you ascertain the axle diameter and thread pitch, ans assuming you can get the cones and jam-nuts off the existing axle's boogered threads without damaging them--- which is actually pretty likely. If you've got an older US-type hub, the axle is likely to be a 5/16" or possibly a 3/8". If it's 5/16", it's probably a 24tpi. If it's 3/8, it may be a 26tpi or a 24tpi. FWIW, brand new Wald axles can be had in both 5/16" and 3/8" flavors, 24tpi. The Wald #188 5/16" axle comes with nutz, bearings, and cones, which may or may not fit your hub but dang.... it's $5 for all that....
http://www.niagaracycle.com/categories/wald-front-axle-set-5-16-wald-excel
But you'll want to measure; there are axles available in most common sizes and pitches, and if you get the right one, your hub's hardware will thread right on.
Another point to ponder: your fork is designed for 3/8 axles with 100mm spacing between the locknuts. Your hub may well be spaced at 91mm. You'll want to pack some washers on each side between the cone and jam-nut to bring it out to 100mm. Otherwise, you'll be pinching the fork tangs, and I could see how that might strip an axle, especially if it's a 5/16" axle.
Shoot me a pm if you got any questions, or need some pointers.