Does your employer have a employee purchase plan? Many large companies do, and you get 10% off new or refurbished Canon cameras and lenses direct from Canon.
Personally, If I were moving from Nikon to Canon, In a case like yours, I'd suggest a Canon RP body with either a used EF lens or, if your budget allows, a new RF lens.
As worldwide sales of cameras continues to drop, so do prices of used equipment. The RP is likely to hold its value better than most. They are being packaged with a EF adapter which allows you to use virtually any Canon EF or even EF-s lens and that includes 3rd party lenses.
You can also get a adapter and use any of your older Nikon lenses, but recent ones with no aperture ring are better off sold and replaced with a EF compatible lens.
This is a case where you might put money into a body first and grow your lenses later.