Another option - the one which I use - is DPCustomMono2 (info link -->
http://www.pgdp.net/c/faq/font_sample.php) developed by the team at distributed proofreaders (pgdp.net) and specifically designed to help with proofreading scanned and OCR'd books and documents. I use it for pgdp work, but I also found it useful in Sigil codeview.
It does take a bit of getting used to though....it is definitely not what you would call "aesthetically pleasing"
It is free, and you don't seem to need a login to download it (I logged out, and was still able to access the download page)......although if you do download it, they may appreciate you signing up and doing a bit of volunteering for them in return
. I can find no information on it re licensing, but then again, I can't imagine anyone wanting to use it in a published document.
Phil