Do you perhaps have a fly fishing friend who has reels with 5 or 6wt lines on them to try on the rod? Or do you have a local 'shop' who might let you try their various weight lined reels to see what works best on it? They all should have a "demo" reel already filled with line for each of the various weight rods they sell for the benefit of the new rod buyer to test cast that new rod they are eying.

Good Luck!