On average, the Chinese drums bring $125-150. I think the $999.99 price is just there to fill in the price to stop someone from ordering seeing as how it's out of stock.
I bought a Chinese drum mags a few years ago for $75. I've seen them recently at a gun show for around $150-$175, but then again that was at a gun show where everything is overpriced. I did see a guy buy a Romanian drum mag for $200 at The Gun Room. Stupid bastard.