Greetings!
Price always varies on the demand. There have been a few players offered for sale recently, but not as many new buyers. This will always drive the price down.
Personally, I think the disk size really does not matter that much when selling (unless you have something extreme). Most buyers can / will replace the smaller 10/12GB drive with something larger if they want to.
The fact that you have the original box, great condition, firesale, etc. is a good selling point. I would guess that the empeg in that condition would go for around $300-350. At least, this is the number I remember (off hand, without looking up previous sales).
The extra wiring harness (I assume you are talking about a full sled, and not just the wire loom) is probably worth about $100-150 additionally. This might be easier to sell individually, but that is your call.
I hope that helps.
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Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs