Yes, there are multiple flights from Thailand to Milwaukee for under ฿49,897. The cheapest flight booked recently is on ANA for just ฿46,997, but on average you can expect to pay ฿47,152.
There are no direct flights from Thailand to Milwaukee, but Cheapflights can provide you with all the information you need to find the fastest route with the fewest stops.
Departing from Thailand to Milwaukee will take you 25h 59m. Both multi-stop and direct flights can be found to your destination and back.
Flying on ANA is currently your cheapest option to Milwaukee, with prices starting at ฿46,997. Another option worth looking into is Japan Airlines, starting at ฿47,091 return.