Here is a sentence from The Wonderful Wizard of Oz:
"That is a first-rate idea," said the Lion. "One would almost suspect you had brains in your head, instead of straw."
I think had might be referring to the event when the Scarecrow suggested that idea the Lion is talking about, but if I remember correctly, I have read somewhere on ELL that the past tense used to be used instead of would. The book was originally written in 1900...
Is that had in the indicative or subjunctive mood, and if that proves to be the subjunctive, could we substitute had for have or would have?