Super compact non tactical mag fed rifle.

[.455_Hunter]

When I was 18, I bought an No. 4, Mk II Lee Enfield (still in the arsenal wrapper), and NIB Norinco SKS, and a NIB MAK 90. I drove a 15 year old car. Priorities are priorities.

Per the OP's question, a used Mini-14/30 might be a good choice with factory 5 or 10 rd mags.