Really depends on how much light you can offer.
Most woody plants need direct sun indoors. Some
may need a dormant period besides. Two plants
that need no rest and can be maintained indoors
are serissa and myrtle. They lend themselves to
tight pruning with medium/fine foliage and small flowers.
Relatively fast growing too.
Please keep your pruning utensils in sharp shape,
nothing worse than frayed stems and torn foliage.
Shudder.

bj

Since yew & box are two of the most popular outdoor topiary plants I wonder how well they would grow indoors in a pot....Here in zone 5 they get a chilling period of course. maybe that need could be satisfied by putting them in a cold garage for a couple months.
They're well suited for topiary because they can be pruned hard and will grow back-not just at the tip but along the stem so wouldn't it be nice if they would work for your project?

I have a potted indoor myrtle topiary. They tend to come quite small, mine is only a foot tall and seems to be staying this way. You can find them in most florist shops. They dont need wire frames because they naturally have dense foliage. Mine is in a ball shape.Im not sure what name to use to ask for them. My tag says common myrtle....But it is a very wonderful and easy to take care of plant... im still trying to propagate it though.

Boxwood is originally from the tropics and the Mediterranean region; I doubt if it requires a chilling period. B. s. 'Suffruticosa' is classic for hedges small topiaries and should do fine indoors provided it receives enough light (equiv. to part shade outdoors). Also keep a lookout for red spider mites.

Yew is also excellent, but I have no experience with it. It is often a companion to Box in English-style gardens and takes shearing equally as well. Yew has the added advantage, I've read, of having the ability to sprout from old wood. Not sure how it would do indoors given is temperate climate lineage.

Both are very slow in their growth which, along with fine and dense foliage, is precisely what makes them perfect subjects for freestanding topiary.

Hope this info helps. Best of luck.