DANG! One of the ears broke off the oil filter cap of my 2007 KLX250s and I wasn't even torquing on it yet.
This cap has channels for routing the oil, and all I see on ebay & Amazon are generic caps without the oil channels.
Found a few US retailers, this part is on back order. China retailers will take a month to deliver!

Who do you use and like best for OEM parts? Need it ASAP.
Adept? Revzilla? Partzilla?

 

As a temporary fix you could buy a thick washer and longer bolt. This should allow you to ride now while the new part is coming.
I usually get my parts from Babbitt's who appear to have the part you need on hand: part 11065-0102.

 

Unfortunately the ear broke in a place where that type of washer solution will not work.
Best option I found for a new OEM cap was for $48 that will arrive in 4-5 business days.