Honestly, I don't remember if they have rebuildables. They've got a lot of good stuff for such a small shop though, and they REALLY know what they are doing, so there is a good chance that they do. Just give them a call first and ask.
I don't like giving the specific names of bad places, but I don't mind sharing the names of good shops. Their name is UVapez.
uVapez Vapors | Merging style with personality
They're a new B&M store so their website is mostly just placeholders without much info, but they have 100% American juices, all mixed in shop. They are more than happy to do custom mixes for you so you can pick any PG/VG balance and have the flavors tweaked any way you want.
Uvapez Vapor - Allen, TX | Yelp
Another place you may want to check out if you find yourself in Plano is a place called Artisan Vapor in Plano off of 15th just east of Central, next to the police station. They've got competitive prices, really good flavors, sell 39ml instead of 30ml bottles, and they have good customer service. They're part of a chain of vape stores, so they're a bit more commercially styled and less mom&pop, but they definitely sell rebuildables as well as a wide range of mods and mech mods. It's my second favorite B&M store in the area.
They also do online sales, so their website is very well done.
E-Cig | E-Liquid | Electronic Cigarette | Artisan Vapor Company
I've been to close to 20 different vape shops in the North Dallas area. These two definitely stand above the rest.