Srx sunroof leak

I’ve had it diagnosed that my sun roof (not drains) are causing leaking in my headliner. It sucks. I found an interiors place who can replace for about $800. Which is not bad but they require that I provide a full sunroof assembly brand new, no used. I’m having trouble. And eBay seems to have pieces and parts but nothing in total. Cadillac quoted about $2,100 to do it but obviously they would provide the sunroof in that cost. Any suggestions on aftermarket full sunroof assembly, brand new?