Not so.
Most ammunition/component companies have pared their product list for 2013 and still haven't caught up with current orders. I've seen no estimate of when the streamlined product lines will return to normal.
To produce 10mm, the companies would have to: take machinery off line, change the tooling, verify the tooling produces what it should, then start production. The cost of the lost production of the current product line would have to be added to the cost of the finished ammunition. This applies to the period of tooling change, 10mm production and the tooling change to return to whatever the machinery was producing previously.