Authentic Fitzpatrick jersey?

Sorry if this isn’t allowed, but I am looking to buy an authentic (original) on-field Fitzpatrick jersey for my boyfriend. How do I go about this?

I’ve been checking ebay but there are only 2 pages of results! They’re mostly autographed (cool but not necessary/more expensive) or youth. Is it that rare to come across one of these? Any advice is helpful. I’m just not good at this stuff. Thank you!