I went to my local bearing supplier. Turns out, the bearings I need for the mains aren't even available through them. She called everywhere. So I had to see for myself. I searched NTN. Koyo & Timkins websites. Nothing of those measurements were available. So I had to order a set of AllBalls. Granted, I pay cost through a shop, but last time, they were only $12 each for NTNs. the size is d=28mm, D=58mm, W=18. Ughhh, this sux. I guess AllBalls has capitalized the market.