Not 100% sure on the head unit, but im pretty sure a 7" will fit fine. I am currently running a alpine CDA-117 head unit, front alpine type r speakers, and a 10" type r sub with a mrp-m500 amp. I think it sounds pretty decent but i still may get a amp for my speakers.
imo, a single 10" type r is enough, and mines in a sealed box. I have had 2 10's in a ported box and it was loud
but lost too much seat room
2003 Ranger FX4, Alpine 10" type R, alpine deck,amp, and speakers, Fog light mod, Hella's behind the grill with dual fog switches in bezel.