5.1, or 6.1, or 7.1 incorporating my existing stereo? (1 Viewer)

Hi - I am sure this has been answered before but I did not find anything definitive via my searches.

I'm a dish network pvr user and I'd like to take advantage of the digital audio out on my pvr as well as my ps2.

I think the max dish broadcasts in is 5.1 so I'd like to upgrade my audio system to surround for the first time ever.

I have great, if entry level, hifi stereo sound with my linn magic-i and keilidh speakers. The linn amp has some available rca inputs and has banana plugs between preamp and amp.

I'd like to use my existing speakers and amp in my future surround system. Is there a range of products for people like me who still want to use their system? Are they a special class of receiver or do I just get a common one and not use the front right and left amps?

My plan is to get a receiver that outputs line level for front left and front right so I can send that to the linn. Then I'd like to use the receiver's amps for the other channels with the possible exception of the sub woofer which may be powered.

My budget is < $1000 including the speakers. Can I please get some suggestions?

Thanks very much for your time.

Brad Sears