Years ago I was fascinated by custom pickups, but haven’t paid much attention in a long time. Why single coil? Are you trying to upgrade a Strat or something? If you go with single coil, get one that is a coil-bucker or something - there is some SC product that is low noise using some technology. Double-stacked pickups that are actually humbuckers but sound like single coil. Something like that.
Anyway, I’m not really a good candidate for advice on this. I don’t care for SC pups much at all. I have one axe that has a coil tap switch that will get SC sound, and I play with that occasionally (and it seems to be low noise), but it’s less than 5-10% of the time. I think it’s cool for leads sometimes, or a funky little breakdown.