I would suggest fuel management and good knowledge of it before messing around with injectors. I'm not positive on the requirement of a fuel pump honestly. I have not done this upgrade to any cars myself yet. I do know on most cars the answer is yes. However I can't recall ever hearing anyone needing a new fuel pump on the wrx to push the new injectors. It may be possible that the stock fuel system is capable of providing enough fuel to use these optimally.
Typically you would upgrade your injectors to allow more fuel for applications where you have already leaned out the air fuel condition of your car. Such as an upgraded turbo.
In near stock conditions the stock injectors are fine and upgrading wont help you out any.
Do a bit of research, as there is much more information out there, and if you decide this is something you want to do, get ahold of me.
I'm not positive how long these will be available at this price.
My distributer offered me a pretty good deal on them as he apparently overstocked.
They will be available at this price for as long as they are in stock. Best bet is to email me when you are ready to buy and find out. Either way I can acquire them at a very good price, it may be a few dollars more by then, but I'm sure it will still be cheaper than the competition.