I have Higgins cave pack and it is quite good. I really like it. I also have his mine cart and tracks. They will do as you like. I'm not sure if you can get the cart to go down or up however. I do have the cart traversing the tracks across a bed of lava. It's going back and forth. The player has to jump in just at the right time in order to go from one side to the other. Otherwise he's dead.
I have just downloaded afrokid's mine pack to take a look at it. He has done good work in the past so I'm sure that it is very useable -- and -- it is free.
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OliveTreeGames