I would also want to know that, but I can provide the following information though: The highest affix is "of vita", so if you find a vita sc you can bet that it also can get the fine prefix too. So the information you want is where is the first place you can get the vita affix to rule out the higher affixes.
ok for scs:
'of vita' requires ilvl 61
'fine' requires ilvl 42
'sharp' requires ilvl 29
'of sustenance (or whatever its called) requires ilvl 61
'of vita' 36-40 requires ilvl 77
'of vita' 41-45 requires ilvl 91 - so for this best to cube a gc from baal,diablo,nith
basically imo its not worth looking in areas for plain and sharp charms - these are low value and easily traded.
For the +life charms, if you want the best scs then ilvl 61 is enough but this will only give you a max of 35 life on gcs. (iirc this is level of nm cows)
for the gcs the best 'easy' to mf are at ilvl 77.
tbh there are not any affixes above this lvl anyway apart from the higher vita (so the usual areas in hell would be fine)
imo its not really realistic to search certain places for certain charms as the chances are tiny anyway and you limit the rolls of other good charms which could be traded.