Sealed: gets you the smallest enclosure which for this is about 150L net, but also the highest roll off.Frequency responseExcursion
Ported: Classic B4 alignment is 360L with a tuning of 16.4Hz. Once I ran the numbers for this alignment with the correct T/S parameters I saw it came close to the 400L of the IXL EB in volume. So you could use the EB design and drawings and using a 6" diameter port, adjust the length down to 38cm for the 16.4Hz tuning. To save you redesigning for a 10% enclosure volume difference, I have used the 400L version in the sims (IXL EB size).
I have also added into the sims a 2nd order (commonly called 12dB/oct) high pass filter at 17Hz to limit over excursion below tuning. All ported subs have this issue. Whether it is a problem for you in practice will depend upon what you are listening to and how loud. There is plenty of content down there in some movies and so it could be a real world issue for you so I'd suggest adding one in.
All of the sims are with 200W of power apllied because that is where the driver hit Xmax with all enclosure types.
First for each of the pairs below is without the HPF, and the second is with.Frequency response
You can see here the excursion increasing dramatically below tuning.ExcursionPort Air Speed
The lower air speed with the filter in place means that port turbulence is unlikely ever to be audible in use.
And finally a frequency response comparion for all three in one graph.