I am looking at a used SWR Redhead online. The seller claims the amp is fine, but the "speakers are going bad". It is for sale for a discount because of this. Could this be a cheap fix with new Eminence Speakers or Cones, or should I stay away. I see these things going for 800 to 1000 used/ 11 to 13 new. This one is for $550, so I'd have some room to work with getting it repaired - however, it will need to be shipped to me...I can't hear the amp. Please advise. Thanks.