how long to run it dry?
That can vary a lot, but 7 days might do it. Temperature, strain of yeast, nutrients, all make a difference. Some yeasts stop at about 14%. If yours is one, it'll never go completely dry. At 1.13 your finished alcohol would be 17%. I don't have much experience in brewing that high, but I would guess it might take longer than 7 days. Personally, I would give up stirring it when the fermentation slows, as I'm not fond of vinegar. When it stops bubbling it's finished.
is that the campden tabs?
Yes. I haven't used them for years, as the types of brewing I do now doesn't require them and I'm on holiday in the tropics so don't have my notes with me. My packet had the instructions on it.
can I use a sanitized painters filter/sock?
LOL. Can't help you there. I'm not a painter. I used to use old sheets, teatowels or cloth nappies. It's not really filtering. It's more like pressing. Once the fermentation was over, I would syphon most of the brew without getting any pulp, then put the remainder into my cloth and wring the last out by hand.... But ..... I only did this for red wines when I wanted to extract the color and tannins from the skins. For white wines I would do this before I pitched the yeast and I would not stir it, or take the lid off, during fermentation.
The wine won't be clear at this point. There are probably finings in your kit to help with that.