For LED lighting, a couple of hundred milliamps is more than sufficient. If you want to use the inductor internally for locomotive track connections, I recommend going with one that's rated at 4-5 amps. For track connections, I pick one rated at 10 amps or more.
- Here's a suitable 285ma 22uh Inductor.
- Here's a suitable 6 amp 22uh Inductor.
- Here's a suitable 10 amp 22uh Inductor.
Note that these can frequently be found cheaper on eBay or overseas sources, you just have to wait a few weeks.