expecting a PC mfg to provide a rescue disk or an OS for a five year old product is really asking a lot in my opinion. If you anticipated the problem ...seems the thing to do would have been to acquire one awhile back.
Might check on eBay to see if anyone has such a disc for sale.
Thought you should know that HP has refused to supply either a rescue disk or a Window XP Media Center Edition (2005 version) for my 2003 HP media center 873n computer. This occurred after the password for XP became corrupted and I was forced to attempt to reformat the hard drive and reinstall XP Media Center. I explained that this was the fourth computer in 10 years that I had purchased from the venerable company and that I was considering buying another in the near future, but apparently they do not want or need my business. After five years they consider computers absolute and do not support OS anymore. Some outfit. Doubt I will buy anything HP anymore. Should you?