I have a store where I'll sell full game assets (aka everything you need for a simple game) from time to time.  Currently the shop only has a space shooter game and candy themed pacman game. 

If you're in a large budget crunch premade assets can be the way to go :)

https://gumroad.com/cosmickitty

and here's the direct link to the space shooter pack:
https://gumroad.com/l/tUoA#

here's the direct link to the pacman arcade pack:
https://gumroad.com/l/VkcPS