[Koha] Suggestions of hardware

Hello I need your suggestions of hardware to implement a koha server, with the following requirements: records: 47,000 items: 157,000 users: 3,000 libraries: 12 For the server I count on vmware virtualization, That operating system ubuntu or debian recommend? How many processors and RAM are needed? and if the number of records and items I recommend mysql on a dedicated server. Thank you very much. -Carlos