pyramids, the difference in price of managed and unmanaged VPS (to be honest, I haven't heard much about "unmanaged VPS" - unmanaged dedicated yes, but not VPS) is so small that its not worth hiring a tech support company just to take care of it. Especially that a lot of companies would do anything that you ask them with the server. Blue mentioned ServInt.com, there is also another company called Dehe.com that will take care of every small thing you ask them.
Best,