She's flying, so has to put the puppy in a crate for flight.Molly is 10 weeks old and she has grown a bit in the last two weeks but she currently measures from floor to top of back/shoulder 33cm or 13 inches. That might help you with your measurements. We are in the UK and I think our goldens tend to be larger than your darker US goldens.
Rather than putting her into a carrier can you not have her sitting on someone's lap for the ride home? Molly slept on my lap and hubby drove. We also had a car harness so could have secured her to a seat with seatbelt if needed. I took some large towels and had that folded on my lap incase of an accident but she was fine, just slept all the way home. Our journey home was just over half an hour.