Your gear seems mostly right. Non-epic gems is not really affordable past T8 btw, they're cheap enough anyone can have those in short time.
You have much more parry than dodge, you may want to shift some to improve your avoidance.
Are you using your cooldowns correctly? As a DK, you have plenty and they seem to need those proactively.
Your spec needs some rework though.
1) Improved Icy Touch. All tanks are expected to maximize their 20% slow debuff.
2) Mark of blood. Mark of blood is a powerful cd and apparently it's also aoe giving it raid utility when your damage intake isn't troublesome. A blood dk will easily recover 1600 hp on every hit they take under mark of blood.
Remember: Blood dks are squishy. Their tanking is powerful because they have both a huge health pool and very fast heals that effectively come just as the hits land, thus masking that damage intake.