These cars aren't like the old fox bodies where you had to match a MAF to injectors you know. Basically stick in those injectors and get a MAF that will support your power goals and just get it tuned accordingly.
The Diablosport MAFia makes the stock MAF good up to 800+rwhp so really there is no need to upgrade the stock MAF. The MAFia is plug and play too and is only $160 at Lethal
Like Eviltwins was saying, the MAF is totally dependent on you expected air flow. Could be all the way from the stocker alone, to the stocker with the Mafia. Or you could go the more expensive route and get the whole mass air sensor from SCT which does not really do anything over the more expensive SCT sensors. That is why the Mafia is good. If you peg the sensor, then all you have to do is turn it up on number and tune off of that. Where as with the SCT you have to put in a whole different sensor .