Where can I buy Glico Curry online in the United States?
Wow, this is hard to find. I know I've seen it in some asian grocery stores, but none of the online groceries that I could find seem to list it, even the venerable H-Mart. No Amazon sellers (usually a good source for odd groceries) right now, either.

Fortunately I found one source for you, eBay seller "hirokojapan" has a persistent listing for Glico Curry Sauce, $5.99 each, $3.95 shipping to the US from Osaka, JP. You select the flavor you want, from Curry, Curry Sweet, Curry Hot, Stew or Rice.

The individual listing link will expire eventually, but future readers can look up the seller directly and see if they are listing a similar item (or message them with a request).