Fixture replacement - need shower wand or diverter

[Water Dog]

I have a client on fixed income. She has a large tub with a 2-handle deck mount tub/facet control. I am trying to locate a replacement system, or each piece that will allow me to install a new fixture assembly over the existing valves - (left/hot - center/faucet - right/cold). All results from the searching I've done lists products with a separate valve/handle for the shower feature... (Not an option). Or a new system that would mount over the hot/cold valve, though this won't work as what we have has the water fill coming from the faucet/center valve. Does have any suggestion for a replacement product? We are trying to complete this without adding a new valve or tearing into the walls modifying the tub. Any help is greatly appreciated! Thank you.

 

[Geofd]

you have to treat this just like a tub/shower you cant legally install it with out a mixing valve otherwise there is a chance for scalding fixed income or not imagine if a young child used that and got hurt...for that matter anyone