If your book is small enough, you could get away with not splitting the html file and using the CSS to ensure a page break with certain headers.
CSS has properties such as page-break-before and page-break after, in particular you can find the syntax for the former here:
https://www.w3schools.com/cssref/pr_print_pagebb.asp
Obviously this can only work if your code is not so large that it would crash a reader, unfortunately I can't tell what your 175 page count translates to in terms of html size.
On a side note, I have a couple of documents that are one large numbered list. The problem with hardcoding the numbers is that formatting the text to have a uniform indent is a pain. Especially if you have some 1300+ items. OL does all that for you. (Thankfully, my 1300+ items were very short, a couple of lines each on average, so having a single html file was not an issue)