i think the change to mamiya mount is $2500. That's just a guess. But you can also upgrade and do a cross platform switch. That keep you value added warranty in tact.
Well, 15k captures just means that it's been shot that much. That's low for 1 and 1/2 years. I really haven't used it much this year. I've had from new so I am the only owner. It's in perfect condition. Always hand carried and with me at all times while working. I am in Los Angeles CA.