Brad, my guess would be at least 10,000, probably closer to 15,000. I've coated about 1,000 .338s, 2,800 30-230s, 3,500 45-230s, and still have about half the pound container left.
I've been paying $15-18/lb for basic colors and as much as $22-23 for stuff like "Kawasaki Green". Plus a couple bucks upcharge for the essential plastic screw-top container and freight charges if you go with PBTB. I consider PC to be VERY cost-effective, especially considering the hundreds of dollars I've spent on bullet lube, lube-sizers, dies, wax, grease, oil, and other related gear. Since you already have the oven and PID, you're going to be out powder cost, a $5 sandwich storage container, a few bucks for Airsoft bbs, and a roll of non-stick foil.