I just spoke with Chuck Miller at Kelton House. They are booked on the date I'm looking for, but he mentioned that all the Saturdays in July are available. Best way to contact him is
keltonhouse@cs.com with ATtn. Chuck in the subject line.,
Basics: Fri or SUn rental is $800 with $300 security dep. Saturday is $1000. This is for a 5 hour time slot.
Hope this helps someone else. See their website for other details.
http://www.keltonhouse.com/specialevent.html