I saw a picture of something similar almost a year ago and decided for Halloween I was going to make it for my son. I tried to do it in the most mustachian way possible and it worked out well.
Costs:
Wood/Paint/Blue tape: Free from work
Wagon: $20 from craigslist
Mouse outfit: $15
PVC pipe: $3
Cheese heads: Borrowed from a friend
Wagon re-sold on craigslist: $40
Total: I made $2 on the costume