I assume the pickups are not working? Both of them? Otherwise I can see no reason to replace them. I have a '64 as well (two if you consider the old Embassy), and only under the most extreme circumstances would I ever replace those magical pickups. I would do everything I could to first get them repaired or rewound. If everything else fails, then I would look for replacement but that would be the very last option. If the person just doesn't like the sound, I would really suggest not messing up a wonderful instrument and maybe buying one that sounds more to that person's liking. Taking apart a vintage instrument like that for no reason other than tonal objectives seems drastic and sacrilegious to me.
Assuming both are not repairable, the Lulls would certainly be the better of the two options as far as I'm concerned. I have no practical experience with them, but from what I have heard they are really nice. The EMGs wouldn't be on my list I wouldn't think. There are a few others that make pickups that are intended to approach that 64 vintage sound. Scott once told me that he really liked Thunderbuckers, and he knows what vintage Thunderbirds are supposed to sound like!