Upcharge for Autographs

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Good evening!  I'm trying to set up merch pages for a musician.  We have a certain number of CD's.  They are one price with an autograph and one price without.  I've found product variants.  However, the solution isn't as eloquent as I'd like it to be.  Does anyone have anything better?  I'd rather a check box that adds an upcharge for the autograph.  Here's what I have.