Keep looking for a vanity - there are some where the opening for the sink is on the end. You can also get a modular system (just like kitchen cabinets) and make it up any way you want. I just bought a similar one at Home Depot - go to their kitchen bath design center. You can get one at any similar place. Now, you may not be able to find a pre-made one-piece sink/counter with the sink at the end, but anything you want can be made up in either formica, stone, or any solid surface material, or you could tile your own.
Galvanized supply lines tend to corrode and get plugged up. If you are lucky, yours are still in good shape (depends a lot on your incoming water). Most people aren't lucky! You may find you need to replace them anyways.