I need to duplicate an arrow I made a few months ago to shoot out of a 41# Kodiak.  The shaft was an anomaly in the 2 dozen cedars I used to build my arrows. The finished arrow is 29" long, 48# spine, 11/32", 125gr field tip, 5" fletch and weighs in at 430 grains.  It flat out screams out of this bow but unfortunately it is the only one I have that is light enough to shoot well. My other dozen of 45-50# spine arrows tip the scale at 500+ grains.

Any ideas on how to get a lighter shaft like this and where?

Any decent supplier will pull shafts of a certain weight out of a large bin. Just ask them; and be prepared to pay a couple of bucks more per dozen.

Thanks for the tip.

Reddogge, call Neil at Hildebrand Company (Washington state) to see
if he can set you up with some light-weight Sitka shafts. I just received some from him & they're the finest shafts I've gotten from anybody so far. Go to the source.

Old York,  have you weighed any finished arrows yet?  I'm using these in only one bow for 3-D and rehabbing my elbow from surgery.

Redogge, as Bjorn said, they'll give you the shafts in the weight range you want/need.  They'll even help you figure out what that is if you give them a call.  Generally, Sitka spruce is just a little lighter than POC, but their weight ranges at a particular spine do overlap.

11.1 gpi for Sitka,
12.2 gpi for POC, and
13.5 gpi for Doug Fir