There is a thread here somewhere about a substitute sealed roller bearing that fits the lower bearing application very well. For less than 10 shipped its worth a look. If you're looking for the upper bearing, I don't know why you wouldn't reinstall what you have. I mean if it doesn't roar when you spin the wheel at the workbench, no problem. I have seen a few that were rusty, balls missing, etc.., but yours looks fine from here.