One of the most luxurious one is one made from an old tea tree that goes for about 100 000SEK per 10 grams of tea but there might be some more luxurious, like the one dipped in gold or the one fertilized by panda dung.
Very hard to say which one is really the most luxurious, but there are a few with prices that look like from another world:
A Da Hong Pao oolong, from the natural reserve area. Especially if it's from one of the few 'mother trees' left. After 2014 they weren't allowed to be picked anymore, so whoever owns some of those leaves can sell it for a fortune.
A pu erh from an old ancient tea tree from one of the six famous mountains, aged for as long as possible. 'Raw' pu erh, since 'ripe' types are cheaper.
Longjing tea from one of the 5 original villages. I've to say that these are pretty overrated. Many surrounding towns with similar soil and climate can produce pretty good ones. In addition, the West Lake region where the 5 original villages are located are neighbouring Hangzhou.....a pretty polluted place these days.