I'd recommend the British Army Service model (BAS). IMO, this is where khuks start performing and aren't just a weird knife. The smaller ones I have (just a few) tend to have very short, thin handles that don't really let you chop. I've often carried a BAS as a hiking blade - it's lighter than larger khuks, but definitely enough to chop limbs for a small fire and clear brush.
Looks like the price range for a standard BAS in Yangdu's deal of the day is ~$50-$75. The one linked above is special, so it's a bit more. Note that deals in this price range are usually "blems" - they'll have minor imperfections that don't affect performance. The exception would be blems that are missing the sheath, or have a damaged sheath. If you're handy with duct tape, you could probably improvise a sheath. Note that there will be no deals, and no sales from HI while she is traveling in the near future, so if you want the knife you should buy soon.
Also, be careful when comparing prices on the web. HI is located in Nevada, so there are no customs fees, and shipping is included. There are several other companies that charge less for the knife, but you end up paying more once shipping and customs fees are included. Plus HI has a great product and great service.