Is there a way to do this without losing range?

The proposal is, for better or worse, quite clear about not providing operator overloading or anything similar in the near future.

You could always offer a method that returns a slice of unique elements, which could then be ranged over.

I don't think there's nearly as much of an appetite for operator overloading as there is for an iterator protocol for range. That isn't to say that the latter wouldn't have a lot to argue over (internal vs. external, etc.) but I think the general usefulness of such a thing would be widely accepted by the community once generics are a settled matter, while I doubt that will ever happen for operator overloading.