The original 400RB does not use just rack ears, the entire side is replaced for ones that have the ears built in ... as SUNN says, VERY hard to find, other than on a head being sold that has them ... I have had several, but only one set left (currently installed on the best lil'old 400RB I have ever played through) ... you could certainly take your sides off, and go to Menards/Home Depot and grab the shortest piece of aluminum angle iron you can find and cut/drill/bolt to your sides ... I have seen it done a few times, probably easiest too, just have to notch around the handle on the one side ...