I'm in the UK and I have been trying to find equivalents to 703 and 705 Owens-Corning in the UK.
Take a look at this datasheet for Rockwool:
http://www.sheffins.co.uk/Literature...xible_slab.pdf
on page 2 you have a list of "types and densities"
on page 3 there is a table of "absorption coefficients"
in a nutshell:
Rockwool RWA45 = 45 kg/m3
Rockwool RW3 = 60 kg/m3
Rockwool RW5 = 100 kg/m3
Rockwool RW6 = 140 kg/m3
You can buy all of these types off ebay UK, just do a search for "Rockwool RW6" for example.
All I need to do now is work out which type of basstrap to build and which desity to use
Hope this helps