I may be able to help you out? I purchased an X4 2 years ago. Due to "stupidity" on my part, I took off out of my driveway with the Display only on my gunnel!! I was taking my boat for service and lost my graph as well. Anyway, I have a 2 year old X4 probe, transducer, display mount, and the power wire for the system. All you would have to do is by the X4 display ($300.00 is the cheapest I've seen it).
I would offer to sell you all that I have mentioned for $200.00. If you buy the display only, you would have a X4 system for aprox $500.00?