Without details of the press and crusher it's hard to tell but it sounds high to me for being used. Check places like midwest and see if you can find out what a new would cost.
<update> I just looked and $300 is what the crusher costs new, so $300 for both would be a great buy.
Its $300 a piece so that high although we dont know what size press it is and that makes a huge difference. I think the pres is a good deal and the crusher isnt. Id get a crusher/destemmer myself! For $100 more plus shipping you could get a very nice crusher/destemmer from FineVinewines or maybe locally with no shipping! This is the crusher/destemmer I had and sold only because I wont be making wine anymore, at least for awhile and if I need one I could borrow a friends. http://www.finevinewines.com/XPListDet1.asp?MM_PartNumber=8054
I agree with Dan. Three hundred for the two pieces would be a great buy. I would go as high as $400 for both and no higher. Keep looking on Craig's List. I have see similar presses for $100.
Does it say whay size the press is, too big and its not right for you. You really need to have these presses filled and if not they dont work that well. If this is like a # 45 press its well worth the $300 itself to a person who will fill it!