Have you heard of this little winery? It's not top of the list for most people, but this is a winery that should be!
They have very VERY good reds and a nice white. But it's their Block 6 wines that you're looking for and these are some that are worth cellaring.
Also, keep a look out for their very rare port. They apparently only make 2 buckets (yes, regular sized buckets) of this stuff a year. I bought me one because the taste is fantastic!

Nice people there too and they know a lot. They're also happy to recommend which of their competitors also make a good drop

Approximate cost: $avg