Brembo big brake kit is gonna cost you $3500 with 15% off from autoanything and a TRD BBK will be about $3000 with the pads and this is without labor and you also need to run at least a 20 inch wheel for fitment.
Like jarrett said, $700 installed through your shop is pretty decent pricing. Unless you're towing heavy loads or planning to get larger wheels/tires, the stock brakes are more than enough to handle most loads.
If you're looking for some better performance without wanting to upgrade brakelines, calipers, etc., then take a look at slotted/cross-drilled rotors (eg: powerslots) and some EBC or Hawk pads.
2010 Platinum, Ballistic Jesters & Blizzaks, XD Cranks & Duratracs, Rigid LED's, Leer 100XQ, TRD SB/SC/Exhaust, V-LEDS, Stebel Big Daddy & Shocker 240 Horns, Escort Redline/Blendmount, Blinder M47 X-treme, Auburn LSD, RC1 grille, Icon stage 2 & TC UCA, AL bumpers, Halos, LED bezels, Prodigy P2...+ more mods. Silver Sky Member#10
2012 Infiniti QX56: Black KMC D2's & midnight grille, Escort 9500ix.
2013 Can-Am Commander LTD with mods.