Rising block for Tom Senior M1

Hi all,
I need a rising block made for my Tom Senior M1 to gain a bit in the Z axes travel.
It would need to be 4 or 5" high and have top and bottom perfectly parrallel.

I attached an exemple from the Tom Senior Yahoo group. This is more a welding job rather than CNC, but I am open to suggestions...
This could be cast, CNC from solid, welded...

Anybody could give me a quote? (I just need 1, but I am sure a quick chat with members of the TS yahoo group would add some numbers...)

Ta,
Laurent