I looked up the Toy Tower specs and found that they are 89Db sensitive and nominal 8 ohms. Given those parameters most 30+ watt tube amps should be OK. You will have to decide on a budget. The Emotiva is relatively inexpensive but most good tube amps are not as easy on your wallet.
I'm thinking of maybe a new Jolida 302 or 502 CRC. Or getting a tube pre for the Emotiva. Just now got the Toy's hooked up and am shocked by how "powerful" & solid they sound for such a smallish floor stander in a 20x20x12 room.