I have seen blank sinks before, where the "faucets and spigots" get cut out on site. Perhaps that is feasible :)?
I am not an expert and wish I could be more helpful.

Ask at a high end plumbing fixtures store.
Call faucet makers.
Ask for a "rough" that uses flex lines to connect the water going from the valves to the spout/spigot.
Then, you can put both handles on one side.

Will a single handle mixer handle do?

As long as the valves and spigot are independently mounted you should be able to do this with ease. Below is a link to the Chicago Faucets website. There are others I'm sure.

Here is a link that might be useful: Chicago Faucets

I have to ask--why does your husband want this configuration? I am just curious.

I am also curious, why a two handle faucet? The single handle temp/volume handles with pull down sprayer are so efficient and nice looking. plus easy to keep clean. Less clutter around the sink, better...

He says that with the two handles on one side, you can still adjust the water temp with one hand and the two handles give better control of the adjustment than the single handle does. I've never tried one, so I can't say whether I agree or not. Personally, I agree that the less clutter the better, but I'm open to other ideas, if they are viable.

I respectfully disagree with your husband that "two handles give better control of the adjustment than the single handle does". Having had both types in various kitchens, IMHO the single handle is better for the reasons Pharaoh gave. Furthermore, when I use my faucet, I am not calibrating to the tiniest degree the temperature. I just adjust the temperature to cold, warm, warmer, hot, all-the-way-hot. I am in a busy kitchen, and flip the single handle to the warmth level I want with a quick movement. Two handles slow you down because you have to adjust both of them, AND you need to have two hands free.

Kitchen renovations have a ton of decisions, and lots of stresses and moving parts. I think you are making your life more difficult than it needs to be by searching this unusual faucet configuration. You will have to explain it to your countertop fabricator as well, and make sure that counters are cut perfectly to fit the faucets.

Your DH is right. The next post from alwaysfixin is right too, about mixing being easy, if you get an expensive mixer valve (they are better than average cost or low cost ones). But I still think that two independent valves operating with one finger or one hand is a Great Way to go. It's going to be more common in the future.

The valves can also be on the same "pillar" as the spout. An Ikea faucet is coming to market soon.

Here is a link that might be useful: Ledskar faucet has two handles on one stem

Make sure the side-by-handles are spaced such that they don't interfere with each other. I like wrist handles so this would be a consideration.

I'd like to see a counter-mount faucet with the hot and cold valve handles on the same vertical shaft. Sort of a coaxial arrangement. Wrist handles, one with the paddle (bent) end facing up, one facing down. These could even be co-axial with the spout. One hole in the counter, handles don't interfere with each other, can be adjusted with one wrist at the same time.

(Maybe that's the Ikea faucet, I can't open the image.)

The ikeafans site link is http://www.ikeafans.com/forums/bathroom/43992-ledskar-201-441-73-faucet.html

Here is the image of another faucet similar to the upcoming Ikea Ledskar
(this one and the Ledskar both have co-axial levers that can be turned by a single finger or by any object.)
.

[IMG]http://i731.photobucket.com/albums/ww316/Davidro1/Dream%20Joy%20water%20delivery%20devices%20or%20faucets/gestospray-3860S-2.jpg[/IMG]

(This one above, with the hose, spray and spring, is a more complicated faucet than the Ledskar.)

Here is a link that might be useful: