Frank, this is great stuff. Thank you for contributing and welcome to
the community :)

We have a small GitHub organization, <https://github.com/schemedoc>
where we work on projects that aim to collect Scheme documentation and
metadata from SRFIs, the RnRS standards, different implementations and
package managers. I invited you along. Would you like to create a repo
there with the code you have?

I also have some very simple code to get SRFI lists for Chibi Scheme and
Guile here:
<https://github.com/schemedoc/temp-aggregator-in-python/blob/master/scrape.py#L252>.
It downloads the source release (.tar.gz) of each implementation and
looks for SRFI numbers in source file names. Your approach of parsing
documentation may be more reliable.

(In case any Scheme implementors are reading this, it would be nice to
have a standardized S-expression file that each implementation could put
in its source release to tell things like what SRFIs are supported,
version number and the like. If you want to work on such a standard,
please tell us :) It would probably be very lightweight, just one file.)

You may already know that the official versions of the SRFI documents
are also stored publicly on GitHub at the
<https://github.com/scheme-requests-for-implementation> organization
(managed by Arthur). We also have an
<https://github.com/srfi-explorations> organization for various
experiments in scraping/re-structuring/validating the SRFI HTML.

Kind regards,
Lassi