That's really up to you. If you really don't want a J-sword then I guess you should hunt something else. But a difficult goal like that will give you good reason to play later on in the game. Trust me, if you still have an item you still haven't found past lvl 150, then it'll give you more motivation to play. Being content with your character or compromising for lower standards often causes you to lose interest a lot faster. So keep shooting for the Sealed-J, you've got 100 more levels to find it. Good luck!
PSU Character:
Izurei - Level 50 Cast, Rank 10 Ranger/Rank 3 Force (Future Guntecher) - Universe 2 or 15
Izurei - Level 50 Cast, Rank 10 Ranger/Rank 3 Force (Future Guntecher) - Universe 2 or 15