power connection to RF circuit

I am designing some circuit that will have an 100MHz amplifier in it, shielded, and wondering how should I connect the power feed to it.
I see 2 options:
-use the same type of coax+SMA cable as I am using for the signal, although the cable is expensive (S9 at Digikey)
-use a simple power wire with a plastic connector at one end, while the other end would be soldered on the RF board PCB. (maybe S0.5)

I didn't want to use the same cable for power feed as I am using for the signal, as it would require 40-100dB (not sure) isolation, while an LC isolation bias-tee does less probably.
With option 2, would it pick up more noises than with the coax option? With the coax I can filter it with ferrite bead and capacitors at both end, and on the way it should not pick up anything.

Some RF amplifiers that have coax signal connection also have the power connection implemented with coax, while some others have different connectors.

The frequency range is important, what frequencies are you operating on? If your power cable collect radiations in the air causing spurs in your operating range, you may think about cable shielding. You can test it using a SA.
Generally speaking, you can use feed-through connectors on your box. As long as you filter the power line on the circuit appropriately(filter+LDO+filter), the power would be fine regardless of what type of power cable you use outside the box. A shielded cable is always better than non-shielded one but a twisted pair work mostly.