Yes, both Capri and Capri II wheels can be used on a Sunbeam. The stock Sunbeam wheels are 4-1/2″ x 13″ with a 4-1/4″ bolt circle and use a 7/16″ RH lug nut; the Capri wheels are 5J x 13 with the same bolt circle and lug size.
The Capri II uses a metric lug. They are visually identical to the late Alpine GT styled steel wheels. Although a spacer of about 1/4″ thickness must be used to clear the drum brakes, they will bolt onto the front spindle. When these wheels are shod with 185/70 -13 tires, they may rub on the inner lip of the front wheel well.