They list for $24.99 for a full set of four. That’s a whopping $6.25 for each string.
Still, that’s a good chunk of change.
The cheapest I’ve found a set of Pahoehoe strings for is $19.95 at Elderly Instruments. However, while a set is $20, you have to pay shipping, so it may not be the cheapest after all. But it’s a good price. Particularly if they’re in stock.