Hi,
When I did my GCSES i recieved a 7 in english language and 77 in combined science, I wanted to remark and everyone told me not to but I did anyways and I managed to go up 2 grades from combined science achieving 8-8 and one grade up for english too -8. I would say go for it, if you are only a couple marks away then there is a higher chance the grade goes up.
Good luck and your grades are great regardless of whether you go forward with this or not