Garden Style tub spout hand sprayer ?

I have a stand up shower and a garden tub in the bathroom. Already have a hand sprayer on stand up shower. Shower is too small to rinse/wash dogs. My garden tub is huge. Would be perfect to wash/rinse dogs off but has no shower head. Only has faucet controls and a curved spout coming out on the exposed side (open to bathroom) not on the wall. Need to know if anyone knows of a product I can use. It is a curved up and over type spout, not a straight out of the side spout. I have seen the temporary ones that will slip over a sink spout but these are not big enough to go over the tub spout.
Any ideas ?

Thanks,
Robert S.

No way, because I assume your "garden tub" is concrete and tile construction, and you would need access to the piping UNDER the valve to modify it.