I had a Thommen X95. Basically, Peter Thommen the legendary designer at F2 set-up his own brand is around 2005 ish. From what I remember the X boards were "Freewave" in the smaller sizes and then became "Freeride" in the larger sizes like yours.
My X95 was a great board performance wise BUT........it suffered from major quality problems and leaked through many pin holes in the deck. From what I understood, Thommen boards were made in a non-cobra factory (Tunisia, I think?) and quality was hit and miss. If your board has lasted till now, it should be fine.
As for fin, I would try the blue or black north shore fins....as they match the footstraps, so you'll look like you are sponsored