Insecure Scripts and images

Anyone have a suggestion on this?

sites I work for use webervations.com for their vacation rentals so people can reserve cabins.

these are part of the scripts to call on calendars to show up on the page, I took off the http: and left the // it still gave the error of non secure items and then also wouldn’t even let the images show up anymore. and they don’t have https options

<script src=”http://www2.webervations.com/calendars/7853_calendar.js”></script&gt;

<script type=”text/javascript” src=“http://www2.webervations.com/calendars/7853_setup.js”></script>

https://ww.wp.xz.cn/plugins/ssl-insecure-content-fixer/