Front carriers for injured dog?

My adult daughter and her high-octane Border Collie go trail running and camping alone quite a bit. Dog got a little injured recently and daughter had to carry the dog for a couple of miles while the dog recovered enough to walk the final mile to their car. For her birthday she'd like a sling for future emergencies, but she wants the dog in front since she goes out with a back pack with gear and hydration for the two of them. Dog is 45 pounds, daughter's 5'6, 145, weight lifter, runner, team sport player. Can anybody recommend a good front-carry sling that is reasonably priced (under $150)? Thanks!