I have a Britax Boulevard which badly needs a replacement cover. I checked the Britax website, and all the Boulevard covers they have available say that they should only be used for carseats made on or after June 6, 2008. The carseat was made in January 2008, will the covers they have available still fit? Or if not, is there some place to buy a cover that will fit? Right now we have the Sutton pattern, but I will be happy to just find something to fit. The ones sold on the other websites don't specify which dates they will fit. Any advice?