Well, I won't be of much help, but I think the writing is on the wall. Mercury made that drive as an option with a 502EFI only. They wouldn't put any more power in front of it. They also only made that drive for a short period of time.
Not sure if parts are available. Also, finding props at a reasonable price might be an issue. If it were me and this was going to be my only boat, I would opt for something with a standard bravo, XR, or imco.
HD