I'd second (third?) the notion that a 4 weight is what you're looking for. Mountain streams ( as I think of streams) and panfish are perfect for a 4 wt. A true 5 weight isn't all that much heavier, but most graphite rods these days punch heavier than the label states. For instance I have a Winston rod that's labeled a 6 wt, but is very, very comfy throwing an 8 wt line.
I'd also note that a very good line can be had for around $60 - check out the Cortland 444 peach lines.
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