Should i evolve this Dratini?
I am struggling to get my hands on a higher iv dratini and debating evolving what has been my best so far. I've attached a screenshot of its possible ivs. He is at 502 cp. I'm at 191 dratini candy(2 months of effort) so i'm well on my way to possibly dragonite number 2 but still haven't found a worthy contender for dragonite no 1. I usually aim for 80%+ for evolutions. I really want a dragonite so i am getting impatient. Should i hold out or go for it?
I have a feeling knowing my luck that as soon as i evolve ill catch a better one. I have caught higher cp dratinis(im lvl 26) but all crap stats.

Answers
The IVs are honestly fine. The lower possibilities are distributed well (attack + HP).
The issue is the low level of the dratini which would need investment of candies and dust.
If this were a level 30 dratini then I'd have no issues evolving it if dratinis are hard to come by, because then you would have a usable dragonite without any stardust or candies spent.
But because it's such a low level it would have to have really good IVs for it to be worth the extra stardust investment over finding an already levelled up one.
e.g if you have a 100% IV Pokemon but it's a really low level then you're choosing to pay like 100k dust and however many candies to have that 10% advantage or whatever it is over an average IV Pokemon that you could catch with an already high level.