In standard Sunsoft cartridge based on 5B chip (except of course Gimmick!) Audio circuit is missed. You can recreate it using unversal board but it doesn't look so professional.
I made a dedicated board which fits perfectly with the board and case. Please look at the second picture.

Attention: I sell only PCB from the first pic. I don't sell the game/cartridge!

--Shipping--
I ship worldwide but some countries are a bit problematic (long time processing customs etc). I set maximum possible handling time but mostly I send item within 3 days.
Heavy big items - please ask about real costs. It really depends on the weight & location.
Declared value - for expensive items I usually sent as Registered Priority Letter with Declared Value.

--EURO--
If you come from Europe and prefer pay in EURO then let me know before purchase.

--More Stuff & Wanted--
You can visit my retro drive where I have a lot of items for sale/exchange and can make a dedicated auction for you. I also like buy from you if you have something from my wish-list.
https://drive.google.com/drive/folders/1m8lvkYSB-DOyFwWIvR6PY0zlqdckpAgQ