Thanks for the advice, it helped a lot. I think the biggest risk is getting a cable that is too thick. The existing one on my Mum’s ‘appears‘ to just be a bit smaller than 1.5mm, so I found this 1.4mm cable on eBay. 2 cables for $5.50 including postage.
Installed it and it worked a treat. If this seller is no loner around, you want to search for 1.4mm brake cable and make sure the ‘block‘ at the end looks the same.
I have seen the exact same cable selling at ‘Specialist‘ websites for $25.00 each - such a rip off. Just taking advantage of our older people.