I've been sort of looking for the same thing. I would just use it to chase quail around the desert so I really don't want to spend $5K plus. If you check out GunsAmerica there are some reputable dealers with a pretty good selection of Uagrtechea's and AYA boxlocks in the $2,500 - $3,000 range. The reputation of both makers are excellent and I don't think you could go wrong with either.
Matt
Matt