In fact, anyone who isn't infantry can solo it right from Lv 1. Pretty sure even infantry can manage it.
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Oh, note you have a maximum unit roster size of 100 and maximum item inventory size of 400. If it gives you a big dialogue box with a button sending you to the scrap screen, you've hit maximum in one of those.
At some point, you'll be able to farm 2-3. The orange nodes on this map give you useful consumables: instant repair and instant recruit.