We have several photographers who come out to the farm and use our trucks for shoots this time of year. We have most weekends booked for shoots until Thanksgiving. One photographer used Hambone's '62 for a shoot with several clients today. They really like the old trucks. Most of the photographers have been digging the '50 GMC 450 (patina and all) here's one of the shots from one of the shoots this year. The other shot is our '49 in an engagement photo shoot last year. We charge the photographer $100 for a half day slot, but they are getting the farm to use, as well, and they can shoot as many clients as they want during their time slot.
The going rate for vehicles for movie and TV work around here is $300/day. If you have to take the truck somewhere for the shoot, you may want to check what the going rate for picture car work is in your area and go with that rate. When we talked about this before, it seemed like $300/day was a fairly standard industry rate. More if they drive it or it is a "hero car."
Word of advice -- most photographers will want the families/kids/etc to sit in the truck. Be sure to remove the key and disconnect the battery (they will find the horn button and the starter pedal ...

) Don't have anything in the truck (including glove box) you don't want messed with or taken. Set parking brakes and chock the wheels. And if you don't like people all over your truck or slamming the doors, then this isn't for you.
Good luck!
John