I know that PIAA driving lights have great light output - but they're not cheap. I've seen them sell locally for just under $200.
If you have a spare set of headlights (I think I'm reading your post right) then try to clean any haze off and try a different bulb - it might surprise you. Are you using buckets/housing that have built-in, non-replaceable bulbs, or are the bulbs replaceable and the housing permanent? I'm not familiar with the conversion other than how it looks. If you're able to replace only bulbs, check out
www.ddmtuning.com for HID replacements. Go with 4500-5000K for the best night vision. I have a 55w 4500K DDM HID low beam kit on my SVT, and it's absolutely amazing. The kits are usually around $40-$70, and are easy to install (about 10 minutes in the driveway for each side, most of which is spent trying to find a good place to mount the ballasts). DDM also has replacements for non-replaceable bulbs, but you have to buy the bucket and the bulb separately, so the cost is more. They might have something you could use as a driving light, I'm not sure.
The fog lights you will find at parts stores have plastic housings, so the first rock that gets tossed at them will likely break the lens and the light will not survive (been there, done that). It's also not legal to drive at night with only fog lights - you might be able to see ok, but you'll likely get a ticket for it. Ditto for driving lights (at least in MT), which fall under the same category as high beams - they have to be off when there is oncoming traffic.
