Mario Gallo,   I am not showing them available on the dell site, so you could reach out to Spare Parts (0870 907 4000) and ask about part numbers    P59VM - 250w power supply9J6JG -  250w power supply VG73K -  fanThat would be where I would start.   
Dear all, there is any possibility to buy spare Non-redundant 250W Power Supply and/or Fan Assembly for R230 Model? If not, there is any Dell statement regarding R230 end of support/end of life? Mario
R230 Power & Cooling Spare Parts availability