Ouch!
Better browse the new and old forum here.
See if you can find a X10SDV, or the Gigabyte/Datto equivalent MB10, from a US seller on eBay who’s willing to ship North of the border. Mini-ITX, 6 SATA ports for your 5 drives (and possibly some boot drive), 1xM.2 (boot or other), x16 PCIe slot that can bifurcate to 4x4 for some NVMe storage on a riser (at least Supermicro v.2 boards: Just avoid early versions with a D-1520 or D-1540; 1521, 1541 and all other numbers should be fine). Takes cheap second-hand DDR4 RDIMM, and generally comes with on-board X550 10 GbE networking which can do 2.5G if that’s what your home network uses.
@Davvo is building a similar NAS in a Jonsbo N1.