Campagnolo hubs should mostly be considered disposable if they are cup/cone. The problem is while you can replace the loose ball bearings and the cone (outer race) the inner race becomes pitted and galled. This race damage translates to trashing new balls then through the ball wear to the cone right back to where you started.

I like Mavic wheelsets which can cone with a Campy freehub. Mavic freehub bushings are a wearable item though.

However, my favorite recommendation is Miche hubsets. You can get a beautiful set of Miche racing box or RG2 hubs for less or around $100. Build up with Campy rims, Mavic rims whatever you want.

The strongest rim I know of is a Velocity Chukkar. You could build a bombproof wheelset with Chukkars on Miche hubs. The racing box or RG2 hubs use easily replaceable 6001 sealed bearings. Replace the bearings when they start to drag a bit, and you bring the wheelset back to "spins as new" which is the opposite of cup/cone hubs. Cup/cone hubs are on a constantly deteriorating performance curve.

You could have a great wheelset for about $100 gotvthe hubd and your cost on rims/spokes. Most good bicycle collectives are going to have some good used Mavic rims and spokes for a deal.