Have the standard bits in the sizes for pen blanks. However, 7mm and 8mm bits are brad point. Search of box stores don't carry them and Amazon only shows sets which I don't need. Your help is most appreciated.
You can purchase singe drill bits for special purposes (soft metals, hard metals, plastics) from either MSC or McMaster-Carr. MSC particularly has "odd" size drill bits. I have a drill bit from them 12.3mm.
<Gloat mode ON> I have an MSC warehouse just 30 minutes from my home and they allow "will pickup" service. I just order something, wait for an hour or two and drive over and get it.
I've bought a lot of drill bits from Victor Machinery. The only downside (if you can call it that) has been the $25 minimum order, not that I ever had difficulty thinking of other things to add to the order.