This can be accomplished by using a controller compatible with external SAS and the ProLiant DL380 G4p. However, the default riser for that model of server is PCI-X only, severely limiting your options. The Smart Array P600 is the only PCI-X controller available with an external SAS connection that would work for your situation. The PCIe riser option (#354589-B21) would give you the ability to use something like a Smart Array P800 controller...
The Smart Array P600 controller would give you a single CX4 SAS connector. You'd need a
CX4 -> SFF-8088 cable to connect to the MSA60 enclosure.
But honestly, this is not worth it.
The G4p ProLiants were a temporary bridge between the legacy SCSI and the new SAS world in 2004. The equipment is too old and too limited to invest any effort in trying to piece a solution together. While it will work, the DL360 is constrained on RAM, so it would not make a good storage server. The P600 is first-generation SAS, so it runs at 3Gbps. SATA drives in the MSA60 would be limited to 1.5Gbps.
Also see: HP ProLiant DL380 G4 SATA support?