You could always try contacting other MFK'ers who have them and maybe someone will point you in the right direction. I recall a few years ago (mid 90's) several of the aquarium resources would refer to G. polyurandon as the FW moray before the popularity of G. tile became more widespread
I've read much the same, they used to be the standard "Freshwater Moray." Now I can't seem to find one anywhere. Wouldn't happen to know anyone who owned one on here would you?
I've seen these for sale locally every once in a while, never kept anything more than G. tile myself though. They seem to come in pretty bad shape just like G. tile.
Yes I do mean E. rhondochilus. They get them in regularly along with G. tiles. All their eels come in looking beautiful, nice plump and healthy looking. They get the White Cheeks in in both the green and black varieties.