My buff Orps aren't laying right now and I do not have any buff Silkies. Wish I could help you out.
However, yes you can hatch them at the same time. Some people do not but I hatch my bantams right along with my standard breeds every week when I hatch. Just remember those bantam eggs will hatch out on day 19 or 20 and standards go to day 21.
Right now I have Olive Eggers, Marans, Silkies, bantam Cochins and BLRW hatching out. Just another hatch at my house. They go in the brooder together for about a week then I separate the littles from the bigs if I can. Sometimes they just grow up together. I have a grow out pen with 4 mth old Marans, OE, Langshans X, bantam Cochins and Silkies. The Marans big old feet get in the way but the Silkies are pretty smart to stay out of the way of those clodhopper feet.
Surely someone will have something at the show that will interest you.