Interleave two randomised sequence (different lengths, one of the sequence is randomised without replacement)

[chiyu1203]

Dear Bonsai community,
I have searched for solutions to this question on the forum but none of them seems to work so please bear with me.
If I only need to randomise one type of stimuli (without replacement), I just need to place a Permutation after the collection of stimuli and then Concat > RepeatCount them. I can do that with the following example.

However, I have two types of stimuli (with their respective elements to be randomised) and I want to interleave one type with another type of stimuli and repeat them for multiple sessions. The first type of stimuli is a sequence with 2 elements to randomize whereas the second type is a sequence with 7 elements. So far, I have placed Permutation after each type (to guarantee randomisation) and use Take > Concat to ensure the two types of stimuli are interleaved.

The downside is that this sequence only allows randomising sequences with replacement. I want the second type to be randomised without replacement so that if the RepeatCount (or the number of repeated session) is a multiple of the 7 elements, I would guarantee to have equal number of elements for the second type. Could anyone suggest me how to modify my workflow?
(Note: I tried to use Zip but the downstream CreateObservable can not take System.Tuple so it did not work)
Below is the attached workflow. Many thanks in advance.
bonsai_question.bonsai.zip