Car Set

I'm really not sure what this is.. It has a red Mercedes-Benz 300 SL number 1073 and then it has a blue with white top Mercedes-Benz 280 GE. On the front hood it says Mercedes-Benz Oldtimer-Service. Number on the bottom is 1044 and then it has a blue trailer same color of the truck number 1668. The box that is carrying these cars is a red plastic 5 1/2 x 7 and on the front of the box it says in German Kinder-modellauto-koffer at the bottom it says Mercedes-Benz Museum.. I’m really just wondering the value of this and the rarity. I haven’t been able to find anything about these nor find anything similar. All I really know about it is that my aunt bought it in Germany at the Mercedes-Benz Museum.. The cars are from Siku, but I haven't heard anything from them.. If you could help i would really appreciate it