MKI Minis used Wilmont Breeden FS style keys for ignition switch, door locks, and boot lock. MK2 and up used a different type for the ignition, but still used the FS keys for the doors and boot. Anyway I have hundreds of FS blanks and can cut almost any key number that matches your Mini. No, unfortunately I don't have Wilmont Breeden blanks but I do have the generic versions. If you don't know the key number, it's stamped on the square shaft of the handle. $5 each plus postage. Buy 3 for $10 plus postage.
Cheers,
Hugh
hockey91dad@hotmail.com