OK, so at some point I picked up some scorpion fighters which have been quite handy at times.. but I'm now down to 3 uses and want more.

Now my problem/question is I'm a Lt. Cmdr, and all the fighters I can find for sale on the Exchange are for admirals. So can i redo that quest I had done to acquire the scorpions, and if so, anyone know which quest/npc that was?

Or perhaps there are fighters for Lt' Cmdrs, just none at the moment?

Yes you can redo the mission. Go to your bridge and access the replay mission console in your ready room. Go to the Romulan Front and then Featured Episodes. If I remember correctly the mission is The Vault.

Just to add, the fighters you see on the exchange are different than the scorpion fighters. The scorpion fighters are a ship device, any ship can equip them (except shuttles anyway). The ones on the exchange are hangar bays and can only be equipped on carriers. They're admiral level items because the only two carriers in the game are admiral level ships (and also Klingon, not Federation).

Why would anyone sell those, there are vendors for them ?

Probably hoping to score some easy EC off of people who don't realize what they actually are and want fighters on their ship. The OP didn't buy any, but it sounds like he did check that part of the exchange intending to.

*sigh* I sometimes forget that some people do such things.

Hmm.. So are you saying the only fighters I can get for my ship are the scorpion fighters from the quest?

yes, every other pet type are klingon carrier only.

Ok thank you for clarifying that for me.