Hitachi hydraulic pump part number

Hello,
can you give me the Hitachi part number of the hydraulic pump mounted on EX40 mini excavator, 1997, S/N: 4GTY 512 W (or 859D001144 ???)?
The pump is NACHI PVD-2B-42 L3 DS-5G 4028A, S/N: 4700081.

Thanks!
Regards!