If you're tight budgetwise, you should focus on finding the front two main speakers that match your preferences, and add the matching center speaker as soon as you can afford it. Don't bother with accounting for the cabling in the budget. If you got a spool of bulk cable lying around, use that. Matching the front three is critical because any mismatches will disrupt the continuity in the front soundstage. Since you already have a pair of KLH speakers, you can use those for the surrounds on a temporary basis. The ultimate goal should be to build a timbre matched system eventually.

With your budget, you got much better options by aiming for the first two bookshelf speakers, and building gradually. These all-in-one speaker packages all present major sonic compromises for music especially, and with home theater you don't need to buy the whole thing at the same time. Patience will eventually reward you with a better sounding system once you're done. Impatience will put you on an upgrade treadmill.