Well I don't necessarily see why trading in a particular currency matters, as people also do barter trade
commodity vs object they buy etc.
Dealing with Turkish currency / Pakistan currency is generally all same
At the end what matter is the value for the helicopter is paid for in proper acceptable format
Example:
If a toursit goes from Pakistan to Turkey they don't go deal with USD
they take Turkish currency to spend it in Turkey
People already follow a established principle
Now if we were dealing with a commodity that trades internationally like oil , or gold or silver etc may yeah I would think about USD
Perhaps this is a good question for anyone who is a Economist by profession to explain benefits of local currency trade vs , a interchange trade with a middle currency
When a Pakistani buys something made in Pakistan in PKR, that money doesn't leave the country, but flows from one Pakistani economic actor to another. While the buyer might have less money at the end of the transaction, the nation as a whole doesn't get poorer from the transaction.
However, when a Pakistani imports something from the U.S., that buyer has to pay in USD, and importing causes USD to flow out of the country. This import causes the country as a whole to be poorer because it has less USD, which in turn means it either has less currency floating in the economy, or (more common) the PKR becomes cheaper (relative to USD).
Conversely, when we export goods, the outflow of PKR (which foreign buyers need to buy our stuff) and inflow of USD allows PKR to become more valuable (relative to USD). This makes it easier for us to import the stuff we just can't produce in the short-term, such as attack helicopters.
That's why trade balance is essential for a healthy economy. You don't want the currency to be so cheap (from a lack of USD) to fail in allowing you to import essentials, such as heavy machinery. On the other hand, you don't want your currency to become so expensive that your goods are too costly (relative to market) to export.
Maximum indigenous sourcing - i.e. where you have alternatives to imports - lets you save on foreign currency, which in turn helps keep your currency valuable and lifestyle affordable for the population. Their essentials (e.g. food, fuel, homes) are locally sourced, they can buy with local currency irrespective of how cheap or expensive it is relative to other currency - mostly local supply and demand dynamics will affect the price.
If you have a local phone maker, and your land doesn't have many rare earth metals, then your 100% local phones will be very expensive at home. But if you have foreign currency, especially a rich currency, you could buy a ton of rare earth metals from some poor country.
Overall, you need a government that is hands on with the local industry in trying to keep up with the market and actively working to achieve a healthy trade and currency valuation balance.
