We took our iHealth test kits the gov't sent us and did a zoom test from our hotel in Madrid on April 25th... check out the website you may also buy the kits from them, the testing service was $24.99. They have a drop down menu that locates any where in the world.
Also if you are sailing NCL they offered free tests to anyone flying out the day of disembarkation ( Athens for us) April 24th.