Servo?
The reason I asked which losi. If it's an RTR they come with a "decent" servo.
jrz590, I think. However, if I was going to spend money on a servo. Airtronics 94357 is the only one worth the money. Put the JR servo in the raven. Put the 357 in the Losi.
You will be amazed at ow much difference a good servo makes.
Beg, borrow or steal. Find a used one. Whatever.
Good luck!