Need sash guides

I just ordered 12 balances but in trying to put the windows back together I am finding that several of the sash guides are broken. I see the 5/8 one on the site but I think these are very slightly smaller than the 5/8 and I ordered 1/2 inch balances originally. I'd like to order 12 sash guides but want to make sure I get the right ones. Thank you. The windows 2 out of 6 that do work are wonderful! No more ruining books holding up the windows to let air in.