Find and Replace in Posts

I have looked for a plugin to perform on WordPress posts the same Find & Replace capability that you have in Microsoft Word and others. Most of the plugins seem to operate at database level and / or require access to phpadmin. I don’t want to operate at database level. In fact I can’t because I am guest contributor on the site where I need this and do not have, want nor would be allowed admin privileges.

I simply want to open a post and do a simple find and replace of individual words such as Catalog for Catalogue.

There doesn’t seem to be anything suitable with a good user base in the plugins directory.

But I can’t believe I’m the only person to need something like this?

I’d appreciate any advice you can give please?