How to make Dynamic lists that also dynamically extend?

I'm trying to build a tool for simulating trade in a table top game, Traveller if anybody knows it. :) The short of it is that a lot of cross-referential math and table references which are performed to figure out the price of goods at certain locations. I've built a lot of my table up, and have most of the work done through the filter function. The last thing I want to do is automatically filter goods that are available at locations so that manual search and input won't be required.

My issue is that there is multiple filters that need to be done and all will be different sizes. For example, I've filled in two different data sets and highlighted where each data set ends (see image). I'd like to dynamically tell Excel, when one filter list is finished, start a new filter list below it so that my data set is contiguous. See image - highlighted cells are where the two (of many more) data sets end, The arrows show where I'd like to tell Excel where the next set should go. These locations will vary wildly because the data sets are not consistent or clean.

This is my current function, for reference

=CHOOSECOLS(FILTER(TradeGoodsPurchase\[\[D66\]:\[Base Price\]\],ISNUMBER(SEARCH(**C44**,TradeGoodsPurchase\[Availability\]))),{1,2})


The **C44** cell is a 2 character search that I search for trade codes, of about 6 different possible trade codes. The 2 digit codes below are searched in this column and the indicated values are returned.


tl:dr how can I get excel to dynamically make dynamic filters?

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