Hi @bpscherer,
I moved your response back into this topic, as you are asking about search criteria, unrelated to the error message you enountered with RESCRIPt, which was solved in the separate topic.
Instead of adjusting the download criteria, you might be able to just filter what you already have. You downloaded all 16S refseqs using the command above. Provided those include enough chloroplast sequences, you can filter those refseqs to grab only chloroplast sequences using qiime taxa filter-seqs, see here for more details:
https://docs.qiime2.org/2020.11/tutorials/filtering/#filtering-sequences
But I am not sure offhand if RefSeqs contains any chloroplast seqs... you should inspect the results. If there are not enough chloroplast sequences, you can consult NCBi taxonomy to determine an appropriate taxid and other criteria for adjusting your query.
But as I mentioned above, I think this might be a bit of a rabbit hole:
... it's worth checking out, but if things don't look promising early on I suggest you don't venture too far in!
Good luck!