To answer part of your question country blues 78's can go for low hundreds to low thousands (of $). I don't know what Chicago blues 78's go for. It must be fun, but it's a well trod field, if you know what I mean.
See Ghost World or Crumb to see the collectors who have gone before you.
Gregg
See Ghost World or Crumb to see the collectors who have gone before you.
Gregg