Yeah, all the border checks to search for money are a joke. You can carry any amount of money in your head. Doesn't matter if it's bitcoin, tether or whatever.

I don't know, ask Iranians. Generic answers would be ATMs (coinatmradar), robosats, agoradesk. There should be a lot of miners in Iran due to low electricity prices, they should be selling. If everything else fails, in Turkey or Georgia finding bitcoin is easier.