Insert a html file without head and body

Hello I am building a new wordpress site for a Bridge competition. The software they use at bridge matches generates really old-fashioned html which in the former version of the site just was uploaded as it was. You find an example on https://www.bc-koppeltje.nl/oudesite/slem.html What I would like is an easy way to insert the html page without head and body tags and if possible without the style attributes, however table tags should be maintained. Especially for the administrator this should be practical. The software can also generate pdf but that is confusing as depending on everybody’s personal pc and os configuration it will open in acrobat or something like that and people who are not too familiar with internet tend to loose there way in the site. I am also thinking about a plugin that generates something like an iframe but still am puzzled, every help would be okay