Australian finger Lime is available here: http://www.logees.com/Citrus-hybrid-Australian-Finger-Lime/productinfo/C2026-2/ Sweet potato plants are available here: http://www.sweetpotatoplant.com/shop/

www.justfruitsandexotics.com has some finger limes, but just the basics. None of the unique colored finger limes, at least not yet.

The soil just under the base of the tree may be damp, but I'm betting the rest of the soil in that pot is bone dry. That tree looks like it's dying of lack of water. If I were you I'd take it out of the pot and examine the soil. Sometimes potting mix can seem wet on the surface but have large dry pockets down deeper. If it's a peat based mix, and most store bought are, if it gets too dry one time, it's almost impossible to re-wet from just watering from the top. It would need to be submerged in a larger pot that does not drain, and really let it soak for 24 hours. Then remove and water normally. Imo, 2 weeks without watering is way too long.

After going to 3 other HEBI found one that had some, bought 3 packages and opened one lime to taste them, it had 4 seeds! I have the remaining limes from that first package in the refrigerator and vacuum sealed the rest and put them in the freezer. I looked up the address of the nursery, and I have a construction roject near them. Next time I need to go I think I might stop by. I heard it can take 3-5 years for a tree to produce ruit rom a seed, and due to hybridization, you might not get the fruit that you want.