Okaygoods is a legit site, it's safe, but before buying it's a good idea to ask them if they have dil in stock. (The people who work on the chats are not very good with english, so don't use any long or difficult words.)
It's always a good idea to use the Virtual keyboard (at least for a part of your password), and use an alt account to store at least some of your cash (also use an alt to buy the dil).
There's a small chance to get cought, but I wouldn't worry about it.