If you can't find an exotics vet, you could see if you could find a vet, who will do some fecal tests. Runny diarrhea is pretty serious and it could be the result of a parasite, so it would be best to see if you can figure what is causing the problem. If it goes untreated, this type of diarrhea can dehydrate a chin and cause some problems.
The only thing that I can think of to do right away would be to get some activated charcoal...mix it with some water and use an eye dropper to get the chin to take some of it. You will probably need to burrito your chin in a towel to get the dropper tip into the chin's mouth. Be careful because this can be messy! Do not give this for more than a couple of days because it affects the absorption of nutrients from the food, basically a chin will get little to no nutrition when it is in the intestinal tract.
You can ask non exotics vets about a few different medications to help. I like Albon for diarrhea problems - it coats the intestinal wall and helps to calm things down. It will do nothing for giardia and other parasites, it will only help to kill off bacteria that may have overgrown in the digestive tract and to help sooth things a bit. (I like the Albon suspension because it is easy to get the chins to take it and easier to dose. The powder is very bitter and would require mixing with water or something else to administer it.)
