Leon ones are bigger by 21mm in diameter. Same size pistons in the calipers, same size pads etc.
Leons have a very flat offset so wheel clearance is more of an issue for spokes to caliper. 305x28 disk is more inset so less caliper clearance for wheel spokes is req'd. (38mm vs 50mm)
£740 gets you a 4x100, 305x28 Disk setup, or you can go to 330x28 size if 2-piece disks, and wheels to clear em (17" minimum)