A look around found this to be a good value are 99 bucks. Replacements look to run a bit more such as http://www.amazon.com/Soundcast-SCS100-SurroundCast-System/dp/B003F7R7SI/ so make that call and see how much to fix.
i haave a samsung ht-510 system with swa-4000 wireless. wireless died.card is good. is there a compatible replacement?