Unless you are trying to pass yourself off deliberately as that other performer, is it likely to be a big problem? I suppose it may depend on how the "rising star" is advised by management. If they hear of you, they could insist on you changing your performance name. If they were really litigation minded they could threaten to sue but would have to have grounds such as evidence of lost earnings, I would think.

So if you want to pre-empt all that, perhaps a performing name could make sense. Do you have a middle name that use could insert the initial? Or a shorter nickname? Or another family surname you could adopt?

And if you are worried about it sounding pretentious then you could post a list of possibilities for a Mudcat vote!