in WI, They run in the 30$+ range. at least from what I've seen from the LFS. Most the LFS I know don't stock spiney eels in. But they are always on their lists, so getting one ordered usually isn't problematic. Try a few of your private establishments and price check around. I made the "mistake" of ordering larger fish.. They are fairly challenging to acclimate to eating. imo buy smaller.
But to answer the 48$ question.. if it was a nicely marked fish, acclimated and eating well, and off live. I would justify the price personally. But since it's online, and you have no clue what the fish looks like, the condition it would come in ect.. no I would pass and do abit of local shopping.