I'd personally recommend either the Alpha Ants Starter Set - C, ANTSTORE Starter Set - glassfarm/arena - classic, or ANTSTORE Starter Set - glassfarm/arena - 20x10.
The Antstore products are slightly better in quality than those from Alpha Ants, but they are also smaller.
Despite from colonies like Temnothorax sp and Pheidole Pallidula, I personally wouldn't go for any smaller than 30x20cm for both the farm and the basin, which only fits for the starter set C from the above listed.
But: You can also make your own setup. Never tested it myself, but should be the same price than one of the offered starter sets...