Dolls don't stand very well without the base, so easel stands are a great option if you don't want the base.
There's another version for regular nendoroids, but both versions come in packs of 3.

Biggest gripe with the easels is they're almost never in stock. The regular easels are even more difficult to find (not counting ones from resellers). You'd think GSC would always have these guys in stock... but nah. heh good luck シ