Boatcoversdirect.com is a local shop here in SC that makes covers for several companies as well custom made for your boat. You can call them on the number shown on the website and they can walk you through every spec you want on the cover. They carry Sunbrella as well as several other fabrics. Everything is in house, you will be talking with the people that make and ship your cover.
Mark 1:17 ...I will make you fishers of men
I'll second the Aurora Canvas recommendation. Top notch quality and service.