I purchased three Indian mudskippers from Franks Aquarium. I was extremely satisfied with the transaction. He was very helpful and all three were in great health. .
My LFS gets them regularly. Most often the small Indian species, but sometimes the larger (more territorial) Asian and African species.
Most fish distributors get them in when available from what I have seen. So I would say your LFS could probably get one for you as long as the distributor has them available.