There is still plenty of distributors for parts. China is also making replacement tips and from reports they are pretty good quality.
Here are a few good threads that I have frequented over on KLOV. They cover a lot of solutions to common issues with desoldering. Some of which you mentioned.
https://forums.arcade-museum.com/sho...d.php?t=451957
https://forums.arcade-museum.com/sho...d.php?t=421210
https://forums.arcade-museum.com/sho...d.php?t=413194
https://forums.arcade-museum.com/sho...d.php?t=393060
Here are a couple of common parts to grab too:
filters - https://www.bdent.com/hakko-a5044.html
Pin for cleaning - https://www.zoro.com/hakko-cleaning-...87/i/G0707817/
Thanks
Blake