I'll be honest, I don't even think it's possible for anyone to even have a golden axe that doesn't live in Japan or hasn't time traveled. The only way you're going to come across one is if you find a Japanese player or a time traveler, and even then, it would take at least 50 individual days traveled buying a sapling each day. Basically, the work involved does not equal the buying price especially when bells are so easy to make.
If I were you and I really wanted a golden axe, I'd time travel myself and get the axe, then revert back. I just don't see someone selling you one at 150k.