And you may have trouble finding a shop that will want to do it at all. I am sure someone will, but like others said, not many will want to paint over others work, not knowing. We all have experienced people who say yeah the bodyworks all done, and it needs a lot of work before paint can be sprayed. Many shops do mainly collision work which is more profitable to them, and don't mess around with completes or working on older cars. They might only do things like that when the shop is slow. The rate for a decent factory type base clear paint job same color, no jambs or bodywork ect, would be somewhere around $2000-3000 and a production type place using a cheaper single stage may be less. Of course there will be rates anywhere under and over that and one place may use better quality materials then another. Also depends somewhat on the area. CA where the cost of living is high and labor rates usually higher may be more then another area where shop rate is 30 something an hour. There is no labor times published for a complete paint job, so It pretty much what the shop guestimates how much time and work its going to be and what they are willing to do it for, if they are at all. I'd go around with the car and get some estimates. Also look at what kind of work the shop is doing.
You could also ask people you know. Maybe they know someone that does some sidework. Also many tech schools that have body repair programs take some cars in off the street. May be hard to get in though, depending on what openings and type of work they are looking for. Where I went though, they only charged for materials. A shop or anyone for that matter who is concerned about there name going on it, is going to be weary of painting over someone elses work. If the paint job fails for some reason or looks like crap, even though it may not be their fault, they are going to be the one who gets blamed and looks bad when someone asks who painted it. Your not going to say I didn't do the bodywork well or prep well enough and thats the reason it looks bad. They'll just say Joe blows bodyshop did it. Even the best job of spraying the paint in the world won't look good if bodywork and prep aren't done well. I remember a dealership I worked for, one of the painters sprayed a escort one of the mechanics cars for a favor after hours. The mechanic did the body and prep and when done it was just a shiney mess.