Dave
I would think that if you like the Wulff lines then stay with that. While I have no personal experience with their line, I have used bass bug taper line from both Scientific Anglers and Cortland and have been satisfied with both. Currently I'm using Cortland's SL in a 7wt bbt. I try and buy local and that's all I could find.
Another alternative may be RIO's Clouser. I have that on my 8wt and have no complaints.
" If a man is truly blessed, he returns home from fishing to the best catch of his life." Christopher Armour