Hello, and welcome, IconoclaST !! (hmm, the fact that you capitalized 'ST' has me wondering... :-o )
I am sure someone here can help with your monitor issues. Some very smart people here on Amiga.org, well, except for me .. :-D
BTW, not sure about nowadays, but Redmond Cable used to have some Amiga monitor cables. Also, there is a site 'pinouts.ru' or something that, listed pinouts for practically everything electronic. Maybe this can help.