Replacing a blind string is easy, and much cheaper than a buying a new shade. And if your trailer is equipped with pleated shades, some more blinds will likely break. There are several sources of new string, here is one if you are interested:
Fix My Blinds (clicky). That site has lots of "how to do it" information.
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There's lots of advice and information in forums... sometimes it is correct. For example, all of my posts are made by a political appointee who got the job as a reward for contributions to my diesel bill.
2011 Jayco 28.5RLS; 2021 Chevy Duramax; Pullrite Superglide Hitch