Another option if your heading out on a trip where breakage may be likely amongst your crew... rent a welder
http://www.cruiseroutfitters.com/rental_gear.html
I've seen and experiences the stick welding with batteries, fantastic budget option and proven in many, many scenarios. If your looking for something a little more predictable and user friendly, it is hard to beat the Ready Welders. Plus side for those of your with ARC welders at home... use that as a power supply for the Ready Welder and you have a defacto MIG machine, run gas or flux-core, aluminum spool, etc. Pretty neat option but I haven't had an ARC welder for 10+ years so I've never been able to try it