The thing about "add-ons" for this version is they weren't even packaged neatly as add-ons, they were individual script, model, sound, etc files, with tedious instructions telling you to "put this file here" and "that file there" and "open this file and add this line" and "open that file, find this line of script, and change it to this"
As such add-ons weren't as big of a thing as they are now, and I don't think anyone has an archive of what little there was. If you want a specific thing remade, you could suggest it
RTB 1.045 itself is easily findable with a google search