Filing a police report for a lost item?

To my great misfortune I misplaced a print that I purchased in Kyoto Station just before leaving the city. I'm so disappointed, because it's really the only significant souvenir I bought for myself. :-(

I have called JR and the Kyoto Station Lost & Found office several times but either it has not been found or we are miscommunicating.

I learned that after a week, lost and found items are turned over to the Kyoto police. I would like to file a report with them, but the English section of their website only has options for doing so in person, and I have now left the country.

Can anyone provide English-language contact information, preferably an email address?

If someone was to be so kind as to contact them on my behalf, the item lost is: Ukiyo-e showing a winter scene, approximately 30x50 cm in size. The print is in a paper envelope which is wrapped in a clear plastic bag. This is inside a tan or yellow-colored plastic shopping bag with the store logo. (I am almost sure) the store is Daishodo. The item was lost on 19/9/2016 in Kyoto station or on the Kyoto subway.

Thank you for any help you can provide.

but the English section of their website only has options for doing so in person

I believe that is because lost items must be reported in person, and at the very least if found it can only be released in person. You will need to find someone on the ground to act as your agent.

Only 18 Sep(JST) listed on Fukuchiyama Police Station/福知山警察署.
http://www.pref.kyoto.jp/fukei/isitu/page/3899.htm
https://www.timeanddate.com/time/zones/jst
You took JR Sanin or Fukuchiyama line?
https://en.wikipedia.org/wiki/Fukuchiyama_Station

No accept by e-mail.
http://www.pref.kyoto.jp/fukei/foreign/kaikei.html
http://www.pref.kyoto.jp/fukei/site/kaikei_f/isituqanda.html

contact form (general) :
https://www.shinsei.elg-front.jp/kyoto/uketsuke/dform.do?id=1358401185...
(no guarantee of reply)

List of lost & found items kept by Kyoto police can be found at:
http://www.pref.kyoto.jp/fukei/isitu/

There are several categories (like bags, envelopes...), but Ukiyoe is a kind of art work, so I think they will update following list when it founds.
http://www.pref.kyoto.jp/fukei/isitu/page/3899.htm

Kyoto police doesn't accepts reporting by email, but some prefecture's police accepts reporting from their websites.
Of course, the best way to find your Ukiyoe is reporting Kyoto Police directly, but it's also valid when you report to another police department.

You can report to Kanagawa Police from following link:
http://shinsei.e-kanagawa.lg.jp/kanagawa/navi/procInfo.do?govCode=14000&procCode=250

Sadly, this site is Japanese only and you need user registration for first time :(
Use google translator, or ask us when you can not understand.

@ Yuton

Why Kanagawa Police?
That membership managed out of Kanagawa pref,too?

@TMK
遺失届(Report of lost items) is valid across Japan.
You can report to any police office in the county.
(See the last question in this site:
http://www.keishicho.metro.tokyo.jp/smph/faq/soudan/otosimono.html#cms... )(Japanese)

According to google search, only Hokkaido, Yamaguchi and Kanagawa prefecure's police accepts reporting by Internet.
So I recommended one of them randomly. There are no special relationship between Kyoto and Kanagawa Police.