Is there anyplace to purchase Disrupter or Plasma weapons for your starship?
I know you can get Plasma weapons at starbase one with exploration credits

Go up the ramp at the Earth Spacedock Shipyard and enter the door up there. That's where you can buy starship equipment with your exploration credits.

You can buy them on the exchange.

But you can also get them for free by killing bad dudes.

I'm looking for other places to purchase them with regular credits

does anyone know of a starbase where you can get Lt Cmd level ship weapons? I went to DS9 but found they only had Cmd level ship weapons.

Try Deepspace K7 or Starbase 34.

spacedock has them upstairs in shipyard for exploration badges 2nd order that you can earn by exploring the hiromi cluster, deeopspace k7 has them for similar points eraned in battles in that sector block, starbase 34 has some I think for regular credits but maybe not mark 3 items and only phaser and photon torpedos no disrupter or plasma weapons ds9 and sb34 both cary odd numberd marks spacedock only has even you can also find them on the exchange but check your prices first, make sure your not overpaying for them

thanks for the info guys.

Nearly everything I've seen on the exchange costs double or more the listed "value"...but occasionally you find something that somewhat reasonable...