Sign up for an account with a third party. There are lots now that offer this service, years ago that was not the case. I can’t comment on other providers as i have only ever used Rinkya to bid and buy on yahoo Japan auction site. Rinkya will store purchases for up to 2 months allowing you to combine and save on shipping cost, they offer both ems and for heavier items sea postage. For larger and heavier items engines gearboxes etc, that need container shipping Import Monster offer a good service if you happen to live in Australia.
Searching on Yahoo Japan auction site, pretty straight forward really using google translate type the model prefix into the search box if searching for Storia/Sirion parts for example type M101s M100s M112s etc you get the idea.Parts are broken down into sub categories engine trans etc.
Purchasing new parts from Daihatsu Japan. Impex.jp offer a service allowing you to purchase parts from Diahatsu,They have a search box that allows you to type in the part number and receive an instant quote. Part numbers for japanese domestic models can be found on the Partsfan website.
Awesome work!!
just to clarify, Rinkya can be used to bid and make a purchase, the the part/s are shipped by the seller to Rinkya, then Rinkya ships overseas?
So this then solves the problem of when a seller doesn’t have international shipping available?
Yep that’s exactly how it works Michael.
I have found one that ships to Germany or pretty much anywhere called buyee, but they have a weight limit of 30kg. Just in case any of the Dutch guys here need to order something 
Just to expand on this - Yahoo Japan now has its own option named Buyee. This can be found on www.buyee.jp
I’ve found the most luck by inputting the required cars chassis code as a search string (ie S13, S510 etc) and then narrowing it down further by part type and $ amounts in the filters. Buyee does not operate on a wallet type basis and therefore doesn’t charge an Admin fee for adding $ to your account like some third parties.
Iv used this guy in the past ( at least 40 times) and he has been excellent.
I’ve been using JesseStreeter for my parts and orders from Daihatsu - been good dealing with him.