Some ingredients are what most cooks would use cooking Asian food. One or two like shrimp paste (belachan) might prove to be hard.
I will upload some photos of herbs and spices used in Nyonya cooking here if i can. Being new, it takes me some time to get around here.
Alternatively, you are welcome to stay with us in my house for a week or two and learn as many Asian dishes I know as you like.
You will see, most herbs and spices are from my garden or kampong (community). I will take you to our wet market where you see for yourselves all the various herbs and spices and maybe substitue with your country's too once you get the taste how nyonya cooking is cook by us.
I wonder where I am going to upload some photos for you, Arwen. Let me feel my way here, I am sure you will get to see and then say "ahh I have this or that. ok?