Definately a MIG welder with CO2/Argon shieldinggas.
Try to buy something between 125 and 150 amps or at least buy as expensive as you can afford (or get away with, without feeling too guilty
)
And get a decent gasbottle (2 or 2.5 gallon)
If you're really unsure of the investment, see if you can loan or rent a welding machine
Ask someone who can weld to show you how the basic settings of the machine work, and what needs to be adjusted for what, so you have some idea of what your aiming for.
Get some different gauges of scrapmetal to practise.
If you're not pleased with the result, grind and start over again.
It's a bit clumsy at first (setting the adjustments, handling the gun) but you'll get the hang of it pretty fast.
Thouroughly clean the metal before you start welding. I like a wirebrushwheel on an electric drill for that.
The only major trouble I find is that the older (like that of the 914) is usually contaminated with rust (even if you clean it well) which will cause a lot of "sputtering" or will burn holes very fast.
It may sound stoopid, but I think welding is fun
cheers,
Jeroen