Long time back even i had plans of converting my Zen VX to Zen VXi, ie. retro fitting a power steering to it but when i asked the MASS people they told me that it would cost me approximately 35K
but a friendly service advisor told me that i can get the whole unit from Chor Bazzar (read as Shivaginagar in Bangalore) and it would work out cheaper and he would do the fitting for around 4-5K. So the next day went to Chor Bazzar and searched the whole place and finally found the whole power steering assembly of Zen VXi but that guy was not ready to sell it for less than 25K...
Finally thought that it is not worth investing around 25K plus 4-5K for a power steering assembly.
Anyhow as of now i have sold that zen and brought a Swift VXi ABS.
If you are so much particular about Power Steering then I think it would be better if you trade your car for a brand new or a second hand Esteem VXi. Because even if you get a Power steering assembly for free and in case the fitting is not done properly you would end up spending more time in the garage than on road....
Vijay