You can get super B complex just about anywhere, drug stores, walmart, grocery stores etc. Anywhere they sell vitamins/supplements. Doesn't have to be labled for chickens, vitamins are vitamins. For moist food you can mix her regular crumbles or pellets with some water to make a mash. If she doesn't eat that you can scramble a little egg, mix in a tiny bit of yogurt to make the supplement stick and sprinkle it on or mix it in that. Most birds like their feed made into mash, and I've rarely had anything but a very sick bird refuse scrambled egg. Some birds like a bit of canned tuna. If the B complex is a tablet then just grind it up first, if it's a capsule just empty it onto the food. The food should be moist so that the supplement sticks to it and she eats it all. You only have to give her a tiny amount of the food, whatever it is, just enough to get the vitamins in her, so use what she will take. The younger the bird the more likely they will be reluctant to try something new.