Your part number is STC4780 - but none of the main suppliers likes of craddocks etc that I checked the websites of have it in stock, however a few of the more marginal continental sites found further down the list of google results for that part number claim to be able to procure it... So it's looking like you might be stuck looking for alternatives, what I did find for you is the automatic brake pedal pad for the MGs of the same era, part number SKE100021, such as the 75/ZT is still available, £9.49 on eBay -
https://www.ebay.co.uk/itm/323329109759 While I don't know for 100% certain that it is indeed interchangeable with the freelander one, I'd be willing to take a punt that rover being rover wouldn't have designed and tooled up to produce a new pedal for one vehicle when they had a perfectly good working design in it's siblings and simply made a debadged cover for the pedal they reused. Last thought would be to go boy-racery and bolt on some of those fancy alloy pedal covers, but for legal reasons make sure you fit ones with non-slip rubber, as bare metal pedals are illegal, however eBay is full of such sets of alloy/rubber accelerator and wider automatic brake pedal covers for under a tenner.