Cerv, if you're using an invasion bow (because that's what that bow looks like right now), we're not sure if you can imbue on those yet (to possibly bring the ssi up to 50).
You're probably not planning on doing that here by the looks, but I wanted to throw it out there anyway.
Now, the bow you listed. I'm assuming it already has been made with ash wood, hence the 40 ssi. You will not be able to imbue on that bow. You cannot imbue on bows that have already used special wood.
What you can do is make a brand new bow.
100pts - ssi 30
150 -balanced
130 -hit lower defense 50
100 -damage increase 50
That's 480 points.
Then you enhance it with ash wood for the extra 10ssi. Yes you have about a 50/50 chance to break it (I've made a ton of these using a fletching 29 normal, non-exceptional talisman), but you can still make it. You can lower the damage and add the hci if you wanted to also.