@Pathdoc RE: HD designation in caption of 77Ltd. thumbnail
1. The SMC patent expired some time ago. Loss of license revenue contributed to the demise of old Pentax.
2. The new nano-particle coating process is a Ricoh/Pentax patent called HD
3. There have been several discussions of whether the existing FACTORY stock of SMC FA Limiteds is exhausted, which if true would suggest a new batch of FA Lim's is called for. Apparently the remaining stock of SMC lenses was shipped to the various regional distributors in 2015 and some of them are out-of-stock on one or two, which can no longer be ordered from factory.
Draw your own conclusion.