advice on engine seal rubber

I'm at the point in my ghia rebuilt that i need to get the engine seal rubber and the firewall seal rubber for my ghia. I want to get the best I can as im not doing this a second time. I know there are a number of companies making them but which fits the best?

West Coast Metric, there are many cheapo rubbers out there and many are bad news.

Try Vintage Vee Dub Supplies for quality parts