I, too, am curious where you purchased your Leo. Any decent store or seller should either have food (i.e. insects) available, or know where to purchase some and could advise you. Leos certainly don't survive or thrive long term on a diet of baby food and ground beef with the occasional cricket.
Where did you get your mealworms from in the first place? Can you not get any more from there?
You can feed the pupa, but considering your situation, I would do what I could to start breeding mealworms instead so you have a long-term solution for your feeding issues. Whenever you get a pet, you have to plan ahead in order to properly care and feed them. Up here, for example, we sometimes run into a shortage of worms or crickets due to inclement weather in the winter which delays shipping. This is something I asked about way in advance, so as a result, I have plenty of feeder insects on hand and a couple of worm-breeding colonies that I regularly stock up on to ensure I could go several weeks without buying new food if I had to. Just because my reptiles "can" survive for awhile without food doesn't mean it's ok to do so, because it is stressful for them when it's not of their own volition.
I would be concerned about the long-term welfare of your gecko if you're running into these kind of issues with obtaining food where you live. I would try an internet search for local businesses or companies that would ship to you, or at least a place that you could drive to in order to stock up on feeders.