To take this one step further, in times of war other things are in demand... such as leather for crossbowmen/archers.
While I like the idea of horses, the comment made earlier that this is a too populated area for there to be too many herds of wild horses is right. But what about herds of cattle? They could belong to either side in the war, or third parties, and it'd be your choice or not if you choose to engage in some cattle rustling for either the meat, or maybe you can sell them to a tanner?
And just one thought further, in the wild west cattle ranchers used to hire parties of bounty hunters to hunt down cattle rustlers... could be interesting if they did that here too if you choose to rustle some cattle.