I'd say RC must be right. My Scots dictionary (thanks again, well-loved friend!) doesn't have bobbycock; the closest entry is bob, "a dance". It doesn't have bumbly, either. Interestingly, a bum-clock is "a humming beetle", but I don't think that's what the quote refers to, somehow. Bubbly is defined as "1 snotty, dirty with nasal mucus. 2 tearful, snivelling. 3 usually bubbly jock a turkey cock". (The italics were the dictionary's.)
Though 'proud as a peacock' is more common in my experience, I have also heard the expression 'proud as a turkey cock'. (The dictionary didn't have peacock.)