Do you have a model number for the router? I don't have a dewalt.
If you don't have a caliper to measure the holes, you can get a rough measurement of the clearance of the threaded hole using drill bits, this can then be compared to a tap and drill chart to narrow down your screw size https://littlemachineshop.com/reference/tapdrill.php
I personally would take the base to lowes or HD and see what looks close.
If you don't have a caliper to measure the holes, you can get a rough measurement of the clearance of the threaded hole using drill bits, this can then be compared to a tap and drill chart to narrow down your screw size https://littlemachineshop.com/reference/tapdrill.php
I personally would take the base to lowes or HD and see what looks close.