A lot of stores don't do restorations on site, but send them out to Kodak. That is what my store was doing before I took over. My store wasn't making much money on the kodak orders and if people didn't like the work they were pretty much stuck with paying Kodak's bill because they won't go back and do any changes to the finished product.
Now that I do them, the store makes 30%, which is more than they were making with Kodak. I am also willing to edit a file if the customer is unhappy which is another bonus to my store. (So far I've had to go back and edit a picture once.) They also get a bit of a faster turn around time because 90% of the time I can get their stuff back significantly faster than Kodak. (Two weeks as opposed to a month or more.) All these factors combined make it much more sensible for my store to use me rather than Kodak. Oh - and my work looks far better than Kodak's as well.
I would do some calling around and find out what stores offer restoration and which don't. Ask the ones that do if they are done in house or sent out. The ones that do the work in-house forget about. The ones that send out to Kodak or some place else you have a chance with. Go to the stores that don't offer restorations or send their stuff out and ask to talk to the manager. Show them your portfolio and give them a brochure with the services you offer, the turn around time, and your price list. Make sure you list in your brochure somewhere all the advantages of you doing the work rather than Kodak or some other company. Ask if you can make an appointment to speak to the store owner or manager to speak about this more in depth and see if they'll go for it.