Hi,
I bought the MLV both plain and foam backed from Super Soundproofing Co. in a 4 ft. width and it is sold by the foot. Link is:

http://shop3.mailordercentral.com/supersoundproofing/

For sound deadening, I am using B-quiet Ultimate, and some left-over Brown Bread, both sourced from ebay.

For hook and loop fasteners, and vinyl adhesive, I am using Sound Deadener Showdown.

I just need time and space to pull my interior and I'm ready to go.
Dave