Washburn WI 14 help

[Project C]

after over 20yrs of not playing I've decided to buy a guitar again. I didn't want to spend a lot so I've got a Washburn WI 14 from Cash Generator with a minor issue.

Two of the string ferrules in the back are missing, which would be an easy and cheap fix as there are loads on Ebay, but I don't know the correct size.

I can't look at the guitar itself as it's on payments so I wanted to order the ferrules before I got the guitar home.

Anyone out there in PH land own one of these and could give me the info on size? thanks