If you're looking for new ones, then I suspect you already have a pretty good idea what they cost. As you say, for an SS bike, you might struggle for a drop-in replacement. Most such wheels that fit Ducatis are either single sided swinging arm wheels or 999RS stuff. Certainly just about every front wheel will be for a "wide track" front-end, making it probably a struggle with fitting brake discs or even the wheel itself. Large axle issue can sometime be overcome with using a different spec bearing, but not always. If you're prepared with dealing with the customisation most likely required, then you might look at some used one from say a gixer thou.
There is one
here Do you really need it for Thunderbike racing?
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