You really need to know the size of the wire you are looking at. If you cannot find anything, anywhere on it, toss it. Guessing on wire is a big no-no.
Since it's only 70 feet, you'll be money ahead by just buying new. Home Depot and Lowes are actually the cheapest on the price of wire that I've been able to find. My Electric Supply houses are more. Their service is better and they have everything in stock, but they are not competitive on their prices.
Aluminum service wire for a Moble Home is fairly cheap. Only a couple bucks a foot if I remeber, and I think it's two lines of 4/0 for your hot leads, one line of 2/0 for neutral and I think a copper line for your ground. I can't remember for sure about the ground wire as I put a ground at the meter pole and another at the breaker box with a ground at each location. I like lots of ground rods.
You can buy a 200 breaker box with breakers for around $200. GE makes a good one that you will always be able to find breakers for. Some of those older Moble homes and even houses have breakers that are just about impossible to find breakers for anymore. Might as well go with new and do it right.
With aluminum wire, be sure to use an anti oxidant at your connections. Aluminum wire has a bad habbit of working itself loose over time without the anti oxidant. It's a black goop that you just put on the exposed part of the wire before you tighten it down. With it, you shouldn't have to re-tighten your terminals. Without it, you will.
Even though the wire is usually rated for direct burial, conduit is always a good idea. Espeicaly if there is any rock in your soil. With such a short run, it's cheap insurance to never have to go back and redo it.
This is pretty basic and there's no real need to hire an electrician. The guy with the license probably wouldn't even bother with it, he'll just send his junior helper out to take care of you and charge you full price for basic information and a job that doesn't requre any specialized skills.
Eddie
