If you have a 25mm wide strap, you need to buy a 25mm loop. Very good quality.
Heavy Duty Cast Solid Brass Ring 8 sizes
West End Buckle Solid Brass Belt Buckle 9 Sizes - 0.5" - 2" inch
Solid Brass Dunham Full Belt Buckle For 1.5" - 38mm Wide Strap Brass or Nickel
Solid Brass Cast Closed O Rings Bags Collars Crafts 13 16 20 25 28 32 38 45 51mm
Solid Brass Pin Belt Buckle Leather Craft Hardware Replacement Accessory 13-38mm
Solid Brass Leather Belt Wallet Band Chicago Screw Back Nail Stud Bind Rivet