Nagoya NL-770G Antenna Question

I just bought a NL-770G Nagoya antenna to replace an antenna I broke. The antenna will go on a Jeep, and I seem to have a problem breaking the antennas, which are very high mounted.

I was surprised that the NL-770G doesn’t have a spring base. Can I swap out the base with one from a prior broken antenna, which I’ve saved? The NL-770G is advertised as coming tuned, which that impact things in any fashion?