West Aussie Glen is parting out an ST. He was above and beyond helpful to me. I think any year ST's electric screen bits would be the same.
Yeah, some time ago now, latest post I found was 2020, most bits, including electric screen mechanism, gone. But I'm guessing he'll see my post and respond if he can help.
Re. the slider, I figure if I get a new one (from Bikequip) I may as well get a pair. Despite the extra cost ($250 to $260, depends on exchange rate at the time) as stripping and reassembly is a PIA (certainly something I'm not looking forward to again), I'm prepared to pay a little more if it saves me a bit of effort.
Having said that, completed mechanisms are in the order of $1000 or more. I'm not going to spend that sort of $$.