Smugglers is good here. For smugglers, I'd start with buying it, unless there is a reason to skip it. If a potion card dominates the board, that's a reason to skip it, because you can't smuggle it. If there are ways for your opponent to progress without gaining cards (e.g. by trashing with steward/amb/chapel), that's probably a reason to skip it. If you have too many terminals, that might be a reason. Cards with on-buy effects, like masterpiece, can sometimes be a reason. If 4$'s dominate the board, and 5$/6$'s won't be bought, that's probably a reason.
Here, the only other terminal that matters is militia, which is just not as good as smugglers. Junk dealer is also not a reason to ignore smugglers, you want several of them, so smuggling them is good, and they produce money, so your opponent will likely buy a card on the turns where he is trashing with them. Gold and Lab, maybe Nobles are good here, all of them can be smuggled. No on-buy effects, no relevant potion cards.
So, there is no reason to skip it -> you should buy it.