What general vicinity are you located, like what corner of what state if not big city? Just wondering if local to me, I could help with some resources. Have you checked if there is a bike co-op near you? (They offer free repair guidance and assistance, used parts stock, etc.)

EDIT TO ADD: As someone with personal experience with your situation, I would suggest as a next aspirational bike, a low cost folding bike based on 20" (406) wheels, find a used one cheap and rehab it:
- When folded, fits inside tent, under bed at shelter (less conspicuous if stashed in soft bag)
- Smallest wheels able to get by without a) internal hub gear (tricky and expensive to maintain) or b) special cassette with 9 tooth high gear.
That was my intro to folding bikes. 7 speeds were adequate but had to walk up some hills. Later converted to 14 speed (2X crank), should have sooner, low enough gears for the hills here. Added racks and panniers, never went back to large wheel non-folding bikes. Also have gotten spoiled by the stepover frame. This brand has gotten expensive, but there's now tons of other brands offering the same design: