If you can brush away the soot and identify the drivers (manufacturer, model number), then IF they are off-the-shelf drivers perhaps you can purchase them from either Madisound or Parts Express at some savings.
If they are not off-the-shelf drivers, then buy the replacement drivers from Aerial.
You might ask your technician if it would be feasible to repair the crossovers, as it's unlikely that all the components are fried (though I'll admit to having no experience with fried crossovers). It might not be worth it considering what he'd have to charge you for his time as compared to just buying the replacements from Aerial. Cloning the crossover again might not be cost-effective when you factor in his time, even if he could determine what the original component values are.
In my opinion, you do not want to end up trying to do a re-design of the crossover for a bunch of different drivers. That will almost certainly give you disappointing results relative to the original, because a lot more time and expertise went into the original than you can afford to put into a re-design.