I notice that you are redirecting to 3rd parties when people "book now", do you have affiliate/kickback agreements with these places, or are you just doing it out of the goodness of your heart?
The company I use to work for maintains an API for integrating with all these systems for booking tickets etc. It is... interesting...in terms of reliability, but it might help you integrate an "on platform" solution. Given that your website is slick, and that the industry is horrendously technologically backwards, you could probably turn this into a decent biz.
API: https://docs.ingresso.co.uk/
Python Wrapper: https://github.com/ingresso-group/pyticketswitch
Disclaimer: No current affiliation, use to work there, helped build the current JSON API, learned the hard way about how backwards these systems are.
Feel free to reach out if you want a point of contact or something