I would go the fibreglass route if I was you as any seat with cloth or vinyl covering is going to get hammered as you end up climbing all over them getting in and out and the passenger seat tends to be your "boot".
Then as this nutty country likes to drip wet stuff from above even when the weather bods claim the big yellow heater in the sky will be on those cloth or vinyl covered seats will be a tad wet and soggy and take ages to dry out.

Buy 'glass ones and pop a hole in them as a drain oh and the best seats?

I'm biased(proud dad bit) but Triton Race Seats are the best in the price range and dare I say it better than some that are dearer.

And all credit to Emma as it's not exactly a girlie thing to be doing, laminating fibreglass seats...