We order many of our hosta from Walters in the 3" cup. They are a bit more expensive than a regular liners, but on average, so much bigger. They are well work the extra money.
Our co-op also buy from Shady Oaks Nursery and QandZ Nursery. will show samples of theirs next. They are smaller in size, but we only have to buy 12 of a variety.
Here are some of the hosta varieties available. Streaked hosta "Sir Richard" and hosta "Special Forces'