Help: Speakers to fill Exceptionallly Large Room?


I'm trying to outfit a large coffeebar with a decent pair of speakers or monitors on a budget. The room is approximately 20 feet wide by 80 feet deep. My current plan is to place one speaker at the front of the space aiming at the bar and a second about half way through the space, again, aiming at the bar. Everything beyond the second speaker will be a "quiet" space for all intents and purposes.

Rules are that I cant use more than two speakers and they have to be wall mountable. I'd like the place to sound good, though I know it will be no acoustic dream, by far. Price range is probably $500-600, $1000 max. Should be relatively efficient, because I'll need some db's to fill the space. Any help appreciated. Thanks.
jaminsky
The Bose 901s hanging from the ceiling is a great idea as critical listening isn't going to happen in this setup anway. I had a pair hanging in a basement 20 years ago. They could fill the place with sound.
Stanwal,

Beginning with the Series 3, the 901s could be driven to very high volumes with a good 75w/ch receiver. They do require use of an equalizer (included) that runs through a tape loop. Finding a modern receiver, integrated amp, or preamp with a tape loop could be challenging.
"they were based on table radio speakers equalized so that their midrange was suppressed to the level of their treble and bass. "

Didn't realize that. That is an innovative design! No wonder their sound was so unique and sought after by many!