OhioHawk, I am no expert but I use Liberty albums for my U.S. collection, though I stopped buying supplements in 1999 and switched to Steiner pages.
The H.E. Harris line was purchased by Whitman publishing: https://whitman.com/stamp-books/h-e...ing-supplies
, when I don't know. Looking at their web site it appears that Liberty I includes commemorative and regular issues, Liberty II includes U.N., U.S. Possessions and Trust Territories, and Liberty III includes all postal stationary, and then there is the Plate Block supplement. When I was buying supplements I only ever bought pages for commemorate and regular issues as I wasn't a dedicated collector of the other material. If I did have FDC's, plate blocks postal stationary, souvenir sheets, etc. I would insert a blank page to mount those on.
On the web site they have supplements up through 2019. You might consider calling or writing them to see what is up.
If you need to make your own pages search "make your own pages" at the search tab and you will find a large number of informative discussions.