Open the light and see who the manufacturer of your recessed light is.

You should select a trim kit form the same manufacturer to avoid problems. Your trim looks very discolored.

You can also order these through HD or Lowes. They don't seem to stock them at the store anymore.

You can use this opportunity to select a better trim style for your cans.

Halo Trim kit

Juno Trim Kit

You should take this opportunity to change your bulbs to something better than those R Bulbs.

The quality of light is terrible.

Get PAR bulbs to fit your fixtures

Make sure you select the best color for these bulbs. Don't go too cold or warm.

We just had all our lights replaced yesterday. Our electrician had advised that many of these lights have been discontinued so good luck. fyi: We tested both the 3000K and 4000k bulbs and much preferred the 3000K; bright enough/not as clinical/when dimmed creates a softer feel.

Sometimes you can find matching trim on ebay but it does help to know the manufacturer, so you don't have to sort through thousands of listings.