That depends on what genus you are referring to when you say Moonflower. If you are asking about Datura, there is one with a pale blue edge. Look at item 7718475830 on eBay.

I just looked at it.............I like it. Also found one called Purple Throat..........loved it more.

If you like the ones with a purple throat, check out Datura discolor. Here's more reading material for you.

Here is a link that might be useful: Legend of Datura