Recently contacted another person who repairs traditional japanese instruments, but the instrument wasn’t their jurisdiction. So I was directed here to message Kyle Abott. I-uh don’t know how to message a particular person on here so… here we are.
apologies, I don’t have the instrument with me as of right now(its my Grandpa’s). this is what i remember about it.
The piece holding the strings at the base of the instrument has just fallen off completely and the strings are definitely pretty old… (Maybe this has an affect on playing it? So probably needs a tune up as well.)
Hi there, welcome.
If you wish to speak to Kyle directly, you can tag him ( @Kyle_Abbott ) but I suspect email is a better option 
That said, I do not know what a Gakusaku Shiki is - and google searches only yield references to this:
The instrument is a Chikuzen Biwa - is that what you mean?
Yes this is it. Thank you for your help.
Thanks for the tag, @Brown!
Interesting! I could possibly fix up your biwa. (I also have one, although letting a friend borrow it as I don’t have room in my home ) When you can, I’d love to see some photos of what you’d like repaired (and the instrument in general). Feel free to post them here or email me at kyle (at) bachido (dot) com.
I’ll be out of the country from next week until middle of September and so wouldn’t be able to do anything until then, but look forward to talking about it all the same! 
Cheers!
Kyle
@Kyle_Abbott
I’m sorry for the late reply. I’d still like to get the Biwa fixed, but it might be a while before I can respond again. Getting a picture is a bit difficult as my grandparents are cleaning up their house.