I discovered this weekend that Cabela's didn't stock 410 chokes, so I went on eBay and ordered a Browning Improved Cylinder stainless steel choke for $27. There are chokes listed for less, but one blogger posted a comment warning me that he ordered a complete set for less, but they didn't fit. There are plenty of chokes out there, but I've never gone wrong with Browning. I would have ordered from Henry but the company informed me that at this time they don't carry chokes. I'm sure that will change in the near future so keep checking their website. Be sure to order an Invector-type choke.
Here's a list of chokes and their pattern percentage: FULL: 55-85% / MODIFIED: 35-65% / IMPROVED: 25-55% / SKEET: 20-45%
The new Browning 410 Improved Cylinder choke
The choke tool that comes with the shotgun really doesn't fit the 410 choke all that well. It works, but the smallest step isn't small enough to fit into the tube. The bottom step is a hair bigger than the outside of the choke, so you need to be careful when rotating or the tool will slip off the slots.
Backing off the installed choke. Once it comes out about a half inch you can back it out the rest of the way with your fingers.
I actually found it a lot easier to use the end of the tool. The choke backed out easily with little effort.
The pre-installed choke is stamped with the Henry logo.
The Browning choke screwed in almost all the way with no resistance, so the tool is only needed when the choke is almost fully seated. When you clean your shotgun, check the choke from time to time to be sure it isn't starting to back itself out of the barrel.