This page of the 1971 Capri sales brochure shows the optional sports wheel. They weren't necessarily a GT item, as you could order one for your standard 1600 Deluxe Capri, and they were optional on the GT's also (possibly also optional on Twin Cam and RS MK1 escorts).
By what you describe, this may be what you have. Price will depend on condition, but as yours needs new leather on the rim it may only sell for $150-200, maybe more if the centre pad has no marks or cracks in the rubber. Will also depend on the condition of the centre badge/disc, and if it still has the rear plastic cover.
A few pics would help with a closer value and assessment of condition.
Cheers
Jamie
Attachment 74901