Monitor B2 series are like $115 and change each.
Paradigm Cinema series or stylus.
Athena may be too expensive except their HTIB which don't come in 7.1
Same for Axiom
Klipsch cinema 10 or quintet. Maybe if you can find a set of their bookshelves cheap. Any of their smaller synergy or reference line. Still may be expensive though.
Yamaha NS-333. Or http://www.yamaha.com/yec/products/H...S_packages.htm
JBL northridge bookshelves.
Anything by Fluance.
Infinity Primus, or the smallest Alphas.
Sapphire Audio is at the high end of that budget.
Wharfedale should compete nicely with the infinity or polk systems.
Polk you can look into. Their pricing is ballpark.
Energy speakers are at the high end of the budget.
Aperion Audio makes a 7.1 package and I'm sure you could ask to leave out the sub and it would be ever so slightly out of budget.
PSB speakers are also at the high end of your budget.
Sony, bose, kenwood, pioneer, panasonic, cerwin vega, KLH, audiovox, Pyle, Technics, Acoustic Research, Jensen, I'm leaving out.
Boston Acoustics, Sonus Faber, Vienna Acoustics, Pinnacle, Niles, NHT, are all too expensive.
Since this is for your in laws, unless they know from home theater any of these speakers will blow them away. So find the one that matches their decor the best or is physically the most impressive.
The Aperion setup seems to be the best set to match your price range. Just get all bookshelves instead of floorstanders and leave out the sub.