As already stated, the Den of Rancor is awesome. Not only are you able to get large amounts of shield skill there, but Parrying skillups should be plenty too.
An alternative you should keep in mind should you find the Pucks too tough is the Boyada Tree. There are Korrigans there which are about two levels lower on average than the Pucks. Which would make them about DC to EM for a 75.
Where in the case of Korrigans, unless spectacularly geared, you are only able to endure their attacks before you're forced to zone, i recon you should be able to take some of the Korrigans out for an extra few points of EXP on top of the skillups. The only downside to the whole camp is that the zoneline is a little walk away, just beyond the waterfall tunnel to the cloister.
I dont actually recall what i capped Shield skill on. I think i got both my last points of Shield and Parrying in Sky all those years ago. There are plenty of T's there to feast upon. It's great for a change of scenery if you're stuck fighting things for a long period of time.
Regardless of that all, Shield Mastery and Reprisal alone should be able to get you to the cap in no time at all, as long as you pick things strong enough.