Are you commited to A-B? They are not the cheapest PLC to go with.
Apart from the normal I/O, do you know if there are any special interface features needed?
The way to find out if you live in a large metropolitan area is to contact the Large electrical suppliers in the area, as they are usually reps. for PLC's and work with local PLC integrators.
If you have a contact at the previous company that would let you have a copy of the ladder (if the same machine), it would save a great deal of money.