I have had one listed on this forum under parts for sale for a month. As of a week ago I have a sale pending but if it doesn't work out I can PM you.
FYI for many years the Husky WR250 and WR300s came with a 5.4 on their Sachs shocks. So check out cafe husky from time to time and I bet you will find one http://www.cafehusky.com/forums/classifieds.27/ Also I have used a Sachs spring on an Ohlins shock so the reverse is possible