There is a good deal available on Kids Woot! today for Halo Sleep sacks. You can choose from a few patterns for just $7.99 each and shipping is about $5. These are fleece sacks and they typically sell for about $20.
If you order more than one, the shipping should still be about $5- so you can get an even better deal on multiples.
If you prefer not to order online, Target has the Halo sleep sacks for $19.99. You can also get a Target coupon for $5 off a sleep sack when you also buy 2 Johnson’s Baby items. Use the Johnson’s baby product coupon for $1 off and you can probably get all 3 items for about $18.00.