I'm not generally one to look a (free) gift horse in the mouth but...flash? Really now?
I understand that porting them to something like HTML5 may take a bit of work, but it would be far better to do than to tell people to grab a SWF player. This isn't one like DOSBox that is open-source and feature-complete.
You could just convert them to self-contained EXE files (contains the player embedded within that 'just works'). Would take a few minutes at most.
Also with the size of the files, 7-zip may be a good idea to offer as a secondary/alternate download for those on limited bandwidth.
I wish you the best of luck with your Patreon endeavors.