I would simply buy one at Amazon with FEWER "predrilled holes" and drill 4 countersunk holes to match my router
e.g.

Amazon.com: PIAOPIAONIU 1 Pcs Aluminum Router Table Insert Plate for Popular Trimmers Routers DIY Woodworking with Rings and Screws for Woodworking Benches Router Table Plate Mounting Base Plate : Tools & Home Improvement
Buy PIAOPIAONIU 1 Pcs Aluminum Router Table Insert Plate for Popular Trimmers Routers DIY Woodworking with Rings and Screws for Woodworking Benches Router Table Plate Mounting Base Plate: Templates - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
www.amazon.com

Aluminium Router Table Insert Plate for Woodworking Benches Router Plate Wood Tools Milling Trimming Machine, Red, 13inches (big) - - Amazon.com
Aluminium Router Table Insert Plate for Woodworking Benches Router Plate Wood Tools Milling Trimming Machine, Red, 13inches (big) - - Amazon.com
www.amazon.com