I remember this instruction about replacing the drier, too.
I have an idea for you that may be worth a try, especially
because of where the leak is coming from. A long time ago when we
used a different refrigerant, I had my air conditioner filled and
one can of refrigerant contained a sealant. This was after I'd
bought the car and the AC system was empty. The fill lasted only
two years. On a long drive, unable to stand the California heat
any longer, I pulled into a large truck stop and had the AC
refilled there. It was expensive, but I never had any trouble
after that. They did something right.
What I'm getting at is that it may be worth trying a can of the
stuff that I'd gambled on much earlier, only with the current
R134. If it seals the pump housing nicely, you've saved a bundle.
If not, you're not out much money.
Hyundai's price seems insane, but it's understandable. As a car
maker, their parts have to go through their warehousing,
stocking, inventory, and inventory tax procedures, as well as
carrying their own warranty. This stuff costs money. I'd go the
other route. My car now has imitation sideview mirrors, and the
quality is surprisingly good, every bit as good as Hyundai's. In
fact, I didn't like the original construction. The only thing
that I gave up with the imitation was heating coils behind the
glass. And since I live near the coast, this feature is irrelevant.
Good luck! Really.