tech: composite vs seperate sync

Hi all

I just dragged in a couple of my old Commodore 1084S monitors to use with my
supergun (on my bench, as opposed to dragging PCBs over to the C128 setup)

One of them has a blown flyback The other is a different 1084S, and only
offers analog RGB with seperate vertical and horizontal sync (the other one
has composite).

Given that a lot of PCBs use composite sync, is there a simple circuit I can
make (hopefully with simple 74 series glue) to seperate the sync if
required?

I know I can always just whack the composite sync into the horizontal sync
and put up with the rolling for testing, but sometimes I like to play

Thanks