An elderly family member has an old rotary dial phone and wants to keep it, but has had many frustrating experiences . . .
What, they about my age I suppose?
When I was freaking with phones, I spent ages trying to make a dial system that didn't need a rotary dial. I even considered pumping ball bearings up a ramp and calling on hoppers dedicated to 0 - 9 that dropped them past micro-switches. Then came the tone system. Magic.
Had phones all over the house. When you'd dial one, the others would jingle. Trouble was, you were supposed to pay for the others, and once had the Rivetess running around the house turning off all the phones as the GPO man phoned on the kosher one. She gave him one of those huge crinkley grins, and he pretended not to notice.
Ordinary phones are to be found in almost every charity shop. Great big boxes of them. Just have one wired in next to the antique. s'what I have to do to fax on my cheap telephone line. Lovely Sony speaker phone $4. Cat not included.