There are two options, but first, these rarely go bad unless the driver is dead as well and created a short, so be sure this will solve your problem before you order one.
We do have new 6200.800, this is a 19V 80W transformer for the 6200, it will give the same end result for a 6100 as it is 19V. These are $60.
We have used 7410.602 transformers, these are $45, they are 19V 60W, the only difference between the 2 is one can supply more watts.