Go to the Flyer base on Planet Parum. Once you select it, go through it looking at every item there. You will eventually find a weapon that is a gun. It is basically a monster on rope. It shoots comets but has low accuracy. You can sell it for 32,000 Meseta.
Once you are a high enough level, go to the Synthesize shop, and buy the Muktrand Board. Get the necessary materials to make it. Go back to your room, and insert the Board to your Mag. For your "???", use the Photon. It will increase the chances of getting the Muktrand. Take the item out. About 84% of the time it will be the Muktrand. Put it in your inventory. If it is anything else, just put it in your storage. Go to any shop where you can sell items. Sell the Muktrand for 392,000 Meseta. Once you have enough money, start making larger amounts of them. You should eventually get enough money to make about eight to ten. You may need to buy the materials, but it should not cost you much.