Assuming the SL has been bought from Oceania, Nigel will source the faders and I will fit them.
Even though the unit is out of warranty, the parts and labour cost is not huge (SOMETHING had to be compromised making a mixer with these features for not much money). Rare is the week I don't have an SL in the workshop for new faders. BTW you can fit Alps "K" series faders into these things and they will last forever.
I sent Nigel an email not long ago lol.
I checked all of the others as requested and only the one seems to have any issues. I did try running some low pressure air over it (as suggested, no cleaner) and the problem is not now as bad as it was, but not cured either (still jitters around on UC but will track with the fader to certain extent).