Budget would be around $600 and it'll going in the cab of an 01 Dodge Ram ext.cab
2 DC Lv2 15s
1 AQ750
1 Wiring Kit ( I believe the AQ750 accepts 4awg)
That should be around $400. Then I would buy materials for the enclosure, your going to build your first ported box, congrats! that should be another $100 or so. Then with the $100 you have left, buy two pairs of component sets, doesn't have to be anything amazing for your first system.
I like this one x3/(lvl3's).