Definitely curious to hear if any community members have found an elegant solution for this - but I would be fairly surprised if they did in all honesty. I'm not aware of any way that you'd be able to do this. I think at the very least you would need to use discount codes, or have multiple variants for a single product that were at different price points.
You would likely have an easier time working with Draft Orders to create orders with custom pricing, and then e-mailing links to complete these orders to your customers.
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