Nice find Heru. 1 3/8" seems the standard which I suppose is aceptable. I mean adjusting from a 1" to 1 3/8 shouldn't be an issue at all.
I would really like a good review on these guys since the place 7th mentioned is in canada(no offense to canada, there are just potential shipping issues) and isn't really on our "to buy from list" yet.
Getting some nice wood and making simple dowel chucks is exactly what I'm doing untill I get some woodalls. Everyday my self control breaks down a little and sooner or later I'm going to crack and just drop my hard earned snicker cash on them. But untill then I'm more than satisfied with my homemades.