Based on your budget and my experience advising travel start-ups and running multi-million dollar travel budgets, I wouldn't recommend the traditional digital channels as they're flooded with travel competitors already. The caveat to that would be if you have something truly unique that can cut through in a crowded space.

Most likely it's a no for Adwords and Facebook advertising.

There are a number of low/no-cost content amplification and inbound lead gen angles I'd be happy to discuss, they'll take more of your time to get up and running, but at this early stage you need to be frugal with your investment, so that's what I'd recommend.

Happy to setup a call if this is something you wanted to discuss further.

Cheers,
Mike