I would suspect most of these vendors are only going to be producing around 1-2Ph/s a month of chips.
Why would you assume that? Thats less than a single 25 wafer batch. Surely the fabs are not that constrained, they do 100s of thousands of wafer starts per month.
As for the rest of the production, while I hesitate to use them as benchmark,
Josh claimed they expect to be able to easily produce over 1000 Monarchs
per day, thats >10PH per month. And have you seen HF's contract builder?
The reason we are only seeing this kind of low volume today is that we have only a single vendor shipping meaningful quantities. One that grossly underestimated demand and/or doesnt have the capacity (yet) to produce more. And thats understandable, wafer production has to be ordered and planned a long time ahead, and they didnt expect the current price explosion. Its possible all the other vendors made the same mistake, although they ordered later and would have had a better view of the market, but either way, its not going to take them all a full year to ramp production to catch up with demand.
BTW, why are you only counting 5 vendors? There is HF, KnC, CT, BFL, Bitmine, ActMiner, Black Arrow, AsicMiner, and probably Bitfury, Avalon. Thats 10; and i may be forgetting some or not knowing about them.