SDA 2 Newbie - Have Questions - Need Advice

OK, so I did something I normally dont do. I went on Craigslist and bought a pair of used Polk SDA 2's off an older gentlemen who is obviously really into vintage audio equipment. Since he had so many pairs of different speakers I figured either I could find a nice set for my 2 car garage mancave or even possibly score a set of decent speakers for my new home theater under construction. He told me these SDA 2's were "audiofile" grade speakers and when he played them in his very small den they really sounded great. I listened to big 15" cerwin Vegas, and a few other models. I was very surprised at how great the older Polks sounded so I bought them for $200. The cabinets themselves are a little rough and they are missing the grilles but I figured what the heck, and he could use the money. When I brought them home to try them out in my garage I connected them to my basic 2 channel budget yamaha receiver I bought specifically for bluetooth to power a set of old pioneer tower speakers for garage listening while wrenching on cars. While at low volumes they sounded great but when I started to crank them the two mid range speakers (on the right channel) started to **** and distort. I immediately got disappointed and thought I wasted my money and should have just bought a new set of Elacs for my home theater at Best Buy. Then I started doing more research. The reviews on these old polks are amazing and alot of people swear by them. I then called the guy I bought them from and wanted to see if he would take them back or trade them for a pair of B&W bookshelfs he had. He told me that it would be a mistake and that the Polks were alot better speaker its just I had a crappy amp connected. He told me about the 4 ohm etc and then I had to educate myself on ohms and power etc. Hopefully the basic receiver I was using to power these is the reason at high volume they start to distort (dont know why I only experienced on the left side) and they had no bottom end. That leads me to my current predicament requiring advice.

Either

A: Shell out $1300 for a new Marrantz 9.2 receiver that has enough power to push these and use them for my home theater and buy a center channel and rears (I have my heart set on a SVS 1000PB sub) that would compliment these vintage bad boys or

B: Stick with a moderate new reciever Onkyo or Yamaha Avantege for around $600 and add a separate amplifier just to power the Polks or

C. Scrap the old polks and invest in a new hometheater sound system with a total budget of $2200 all the while wondering if I blew an opportunity to have a better system with the vintage polks, or

D : Dont use them for my home theater, keep them for the garage and wait for a decent used amp to connect to my basic yamaha stereo receiver.

If I was going to keep these Polks as home theater front channels, what would be a good center channel that would go well with these? I was always told that the front 3 speakers should match brand and series etc but these are old.

Lastly, I realized that these Polks should have came with an interconnected cable that wakes them up even more. Would I need that in a 5.1 set up or will that mess up the tech of a new receiver etc.

Overall finished basement size is 25'x16' but the area that my theater is going is about 18'x 13' but is open to the rest of the overall finished side.