I've been browsing around looking for various Rory pieces as I mainly need shirts to call an outfit done. So today I happened to stumble across the LAST thing I was looking for but it's a positive ID all the same. Rory's check/plaid shirt from the Comic Relief Time/Space episode!
Reference picture:
The ID:
Gap check/plaid classic shirt in mustard/navy *As mentioned in the comments, the white/yellow check lines are switched around, I wouldn't argue with this shirt though, it's one of those odds and ends common with plaid/check shirts*
Like most other shirts for both Amy and Rory, this shirt is out of stock/prodution everywhere. I managed to find one on eBay a bit smaller than my average shirt size but bought it all the same as I got it fairly cheap.