Sunbrella cover re-waterproofing?

[Triple]

I need to re-waterproof my storage cover that is made from sunbrella material, the water is soaking through and dripping down of the inside where it touches anything.

I know they recommend 303 fabric guard. It's a full cover for a 21 footer so I would probably need to use a big bottle of the liquid gold -
http://zoxoro.com.au/Products/303-30607-Fabric-Guard-128-fl-oz.html?gclid=CIWlhP7xmsUCFUkrvQodEB4AOQ
Anyone know where I can get it cheaper than that (most places from us won't ship it) or has anyone used any other products that still work on sunbrella material that lets the water bead AND still breathe?
3M scotchguard?
Cheers.

[Rip it up]

Head to the local camping stores and ask about canvas treatments. There should be a 5L bottle of white liquid. Looks like thin PVA glue. But it works excellent.

I've used it on cavnas tents and sailing wet weather gear. Totally beads the water away.

http://images.tapatalk-cdn.com/15/04/29/e99342d0c1621699d239ba3d8c91344f.jpg


Damo's dodgy boat building repair centre.

[Triple]

I've been told not to use that aqua proof on sunbrella material as it stops its "breathability". Anyone tried the Sun brite waterproofer with ptef as it says it's sunbrella safe and alot cheaper than 303.
http://www.ausfish.com.au/vforum/attachment.php?attachmentid=108578&stc=1