Beyond the easy answers of replicating the machine itself or covering basic needs, I think it would be interesting to make a super computer with a small form factor capable of mind uploading. Then you print a replacement body in a position that fits within a cubic meter and presumably you can extend your life for a bit. A simpler alternative would be to replicate medicines that have been shown to extend healthspans in the short term and just take them in the recommended dosage when you need to.