Evaluations for the 8 Koitsu prints
Evaluation 1
After taking a look at the images on your web pages, I come to the conclusion that only one of the prints was produced in the lifetime of Tsuchiya Koitsu, who died in 1949. That's the one that you are calling "Kiyomizudo in Ueno". The seal on the left reads "Han Moto Tokyo-do". Not much is known about this publisher except that they were in some way affiliated with Doi and produced prints from Doi's original blocks. It is generally accepted that prints with their stamp were produced before the war.
The ones with no publisher seal are generally thought to be done after the war, perhaps in the 1950s. This is a grey area, to be sure, but I've never heard anyone advocate that these are early prints. The keyblock lines on each of them show signs of wear which are consistent with later editions.
All the rest of them which contain a publisher seal have the seal of Doi Eiichi, the son of the founder of the company, Doi Teiichi. These are all later editions probably not earlier than 1980. The timespan for the seal of the printer Seki is from 1965 to 1995.
Check out this web page for an interesting discussion of Doi seals by Andreas Grund and Thomas Crossland.
Evaluation 2
All print are real woodblock prints, but most from recut blocks
1) Kameido: posthumous print, Doi Eiichi, Harada, Seki, made in the
70/80/early 90ies
2)Miyajima: no seals, probably posthumous
3) Matsushima: Doi Eiichi, Endoh, Itoh, posthumous, around 60/70/80
4) Kiyomizudo: rare seal "Hanmoto Tokyodo", who made prints commissioned by
Doi, probably prewar
5) Akashi Harbour, Doi Eiichi, Harada, Seki, posthumous, see 1)
6) Yakitsugahara: no seals, posthumous, very recent strike, bad
registration = worn blocks
7) Maiko Beach: ditto
8) Miyajima Rain: no seals, posthumous
Many posthumous prints without seals are of low quality and probably found
a shady way to the market without approval of the publisher.
Email: Ross Walker