Is it acceptable to contract the phrase in the subject the way above (at least in a spoken English) without raising eyebrows?
Using the contraction is a matter of the author's style and the type of writing. It's use is acceptable to reproduce the compressed speech of conversation or first-person narration. From Misadventure: Monologues and Short Pieces by David Marguiles:
Prolly not. (Pause.) Threw me outta school 'cause of it. Least if I'd've been nineteen, least I'd've had a diploma from high school, least I'd've got a real job, maybe. They dint wanna give what you call special attention. Nowadays it's different.