It may be difficult for you to find 4m trees locally since they are a North American species. If you would like to start some from seed, check out my
info page, and then send me a private message with your mailing address. I collect Taxodium distichum seeds in the winter and start them in the spring. If a tree grows well in the first year it can be 1m tall at the end of the year, and it may take 5 years to get to 4m.