IF you have the patience to wait, you can get from newegg these sale prices. You'll end up doing piece by piece but worth it. The sales are fairly regular, you just need to watch closely AND sign up for their regular emails.
All Polk Audio, all no tax (depending where you live), and all free shipping
Monitor 60's can be had for $99.99 ea
CS2 Center - $99.99 ea
Monitor 40's - $99.99 pr
PSW505 - $179.99
NOW, that's $580 so I'm not sure if your budget of $500 is firm. If so, be MORE patient
Get the 40's, the CS2, and the PSW505 and some 30's for $59.99 making the total $440 and when the budget allows, get the 60's and move the 40's to surrounds, and the 30's to back and you're ready for a decent 7.1 (which your receiver supports and probably the route I'd take in the situation you described). OR start 3.1 with the 60's, the CS2, and PSW505 for $480 then add the 40's when the budget allows. Many other combos like 4 40's the CS2 and the PSW505 for $480, ...
ALL will outperform the options you posted, BUT that is an opinion and we've all got one