What is the Make and Model of this speaker?

I can't tell by your profile where you are located. If you happen to be in CA look for a pair of RSL 3600s. They were manufactured and sold there and come up fairly frequently on CL or eBay. You will be astonished by the SQ at that price level for vintage used compared to almost anything.

If I were you I would look for a pair of DCM Time Windows. You will find a couple listings on hifishark (ebay).

Under 500 the Time Windows would be a good choice. I have a pair I'm not using in excellent condition but I can't ship.

Those quad specs seem odd.  IThe one speced must have a very weak power supply. If so, the quad mode should work better.  My Fisher had 35 wpc x 4 or 90 wpc x 2.  My old Bryston 100 watt amp (3B) is 100 per in stereo and 400 in mono, i.e. two of these would be 100 x 4 or 400 x 2.    

I LOVE my Dahlquist 20s. I’d love to get a pristine pair of 10s.