Nick just done the numbers for us...
The transistors help to increase it a bit, but needs to be used with caution.
But you want too many leds.Have a look at special led projects out there, designed to power the leds properly, or just buy one( wont be that expensive anyway).
I, for one, thought that you just wanted to understand the dynamics and code of it all ! Never thought you wanted to keep adding endless numbers of leds lol lol lol What are your plans anyway???! Light the local street party or owt ?!? lol