Sugarshed, I'm not familiar with the Marquis but I assume it has 2 woofers per speaker in a D'Appolito array since John Dunlavy favored that design. I would examine the other three woofers to identify their brand and model number, then find a replacement based on that.
Duntech made a big deal over matching and measuring individual drivers and keeping that information on file. This would allow them to match any given driver if a replacement was necessary. I suspect, but am not certain, that crossovers were then tailored so that response measurements fell within their specs. Fortunately for you, this may be less important for a woofer than for a mid or tweeter.
So the point is, even without matching the original woofer for factory specs, a replacement should at least be the same brand and model as the original. Your odd matched woofer is likely compromising the potential sonics of a fine speaker.
From what I know, Millersound is as good as any speaker repair facility you can find. But I would not bother replacing the surround on one driver that didn't match the other three.
Duntech made a big deal over matching and measuring individual drivers and keeping that information on file. This would allow them to match any given driver if a replacement was necessary. I suspect, but am not certain, that crossovers were then tailored so that response measurements fell within their specs. Fortunately for you, this may be less important for a woofer than for a mid or tweeter.
So the point is, even without matching the original woofer for factory specs, a replacement should at least be the same brand and model as the original. Your odd matched woofer is likely compromising the potential sonics of a fine speaker.
From what I know, Millersound is as good as any speaker repair facility you can find. But I would not bother replacing the surround on one driver that didn't match the other three.