I love my syrians. Only hamsters I have ever had. You can get willow tunnels or plastic bendable ones that are big enough for hamsters.
https://www.zooplus.co.uk/shop/small...tunnels/169939
https://smile.amazon.co.uk/gp/produc...?ie=UTF8&psc=1
you can tie the willow tunnels with jute or sisal to the cage sides if it's a metal bar cage and the plastic tunnels you can puncture holes in the ends and tie from the ceiling or submerge under bedding.
I appreciate you are not in the UK, but hopefully you can find something similar near where you live.