Make sure you get an inverter. They have heaps more power. I have a $300 ebay chinese tig and it works really well. I have welded all the stainless and mild steel on my cobra with it. Only problem was the gas fittings were plastic. I swapped them for brass and it has been perfect ever since.
I would just buy one of the many on ebay.
RITEWELD NEW MIG 195 AMP GAS / GASLESS WELDER 15 AMP PLUG | eBay