I am aware that I'm a bit late to respond, but if you're still interested, yes, I do know of some other seals.
@ElliotFrisch mentioned Rassilon's seal being called 'Prydonian'. I have done a bit of research on Doctor Who and have found that there are six Gallifreyan chapters, or six chapters of Time Lord society. Three are academic and three are pragmatic.
The Academic Triad are the Patrex (or Patrexes) Chapter, the Arcalian Chapter, and the Dromeian chapter. The Pragmatic Triad are the Prydonian Chapter, Cerulean Chapter, and the Scendles Chapter. They each have their own seal. Each chapter had a different founder. The Prydonian Chapter was founded by Rassilon, which is why the seal is called the Prydonian seal as well as Rassilon's seal.
This is one picture of Rassilon's seal shown for all the chapters, but using their colors. Usually each of the different chapters are shown using Rassilon's seal like this, but that is because Rassilon was the President of the High Council, and so the Prydonian Chapter was then considered the most important, in a way. They do have their own seals, however. In order, Rassilon's seal, Omega's seal, Lazuline's seal, Apeiron's seal, Eutenoyar's seal, and Pandak's.
I've accidentally put the images of the chapter seals in the wrong order and I can't seem to fix them, so just to clarify, the names of the seals go with the order of the first picture, left to right.
Credit goes to Rory Prisogika for creating the non-canon seals.