VanTX is a master at repairing arrows with a long splice. You do need more shaft length than the two pieces of the original arrow.
In this case, all you really are able to salvage is the fletch, crest and nock. You need a new piece to splice on the front.
As far as being safe, I am a radical. My reasoning is that a glued joint in wood is stronger than the wood, AND, if you splice a new piece to the old piece, the grain in each will diverge from the other enough to reinforce both. If the shaft holds up to spine testing after repair, it ought to holdup to paradoxing around the boe handle.
BUT, it's your hand and your results may vary!
Philip Rounsvelle was recommending the practice way back in the early part of the 1900s (remember them?
Here's a little food for thought. I have shot this arrow enough to know that it's only drawback is that cherry and walnut are too heavy.
Reparrow man