How to create a Drill down filter/formula

I am a district manager for a team of people that merchandise retail stores. We pay mileage and travel time. So as you can see in the attachement I have worked out all possible senerios of what store my employee can go to.

What I am wanting is a place where I can enter store 1 (say 1003) and then enter store 2 (say 1004) and it will sort through this list and give me the distance and time of travel....

If this can go up to seven locations would be great.

See the issue is that it will have to sort through the list on its own and add the totals together.

I hope this is a good enough explanation.


I have boxed off an example of what I need it to do. The yellow area is where the formula would have to be...

Any suggestions would be great...If I am looking at this wrong.