Called a "pot joint" due to its round, can shape, this is actually a type of CV joint on the inner end of the drive shaft as fitted to all Minis from 1973-2000. Rubber boot is included. Sold each, two (2) used per car. Aftermarket. Ref: GCV1102, GCV1102MS, ADU4378, DAM667.
Consult a shop manual for removal from the gearbox and the shaft.