You might want to check a few places for VW GTI fabric. That looks really similar to some of their stuff, but I've never seen it on a stock e30. Maybe it's a custom job? Looks like the entire 'vert interior was freshened up...superb!
Or update it with some alcantara bolsters!
Reminds me of the old 924 & 944 Recaro buckets too, especially in the Martini Edition. Porsche guys have superb resources for restoration, but they're not cheap.