I don't think any moves have to be made.
Can an outsider be ready in a couple of practices?? Unlikely.
Driver, Jennings, and Jones can handle it. You may adjust for pressure by keeping an extra blocker instead of going 4 wide.
Havener, Lee, Ahman Green for dump offs (Grant or Jackson if you have to).
Which is quicker taining a new guy or Nelson being back?
Elevate a 2nd year practice squad guy if it is really necessary.