I've bought a lot of equipment that looks much worse than this and and they are still working today. I've got a Lincoln that my Dad bought in the mid 50s and it still works as good as it did then. This Miller appears to be from the 1990's and it's appearance is really good so I'd have no problem buying it if I only was closer.
Recently I've been buying old equipment for pennies and with little work putting it back out on the market.
I'm glad there are people like you out there because it makes this a lot cheaper for me