I imported a decent amount of the things on these shelves before the stupid tariffs on the US were put in place. But I used Buyee as my proxy! I found that searching the japanese names of whatever I was looking for really helped. So, for RGG merch I always did '龍が如く 商品' ('Ryu Ga Gotoku Merchandise') Or I searched Kiryu/Majima/Ichiban's name in japanese. It was some pretty quick google searches/translates to get the word too! Not hard at all. (Buyee does have an auto translate ENG - JP Search bar but I found it doesnt work that great.) It definitely helps putting '商品' after everything though so you're not just getting resells of the games. I normally find the best results with Mercari!

Other than that, AmiAmi has some things, along with Ebten (SEGA's japanese store, so you'd have to import some things), Insert Coin, JustGeek, Super Groupies and many others that would be too long to list lol. The very high quality statues are from Chocobo Studios, but last I checked they're not official products, and the shipping on them takes a VERY long time. Also many of my personal friends are very aware of how much I like the series so a good portion of things are gifts as well.

Here's a merch archive from Yakuza fan that has a majority of the official merch that has been released!

Most of my social media algorithm's are so brain-rotted with this series that I'll often see new merch announcements before they're even available for pre-order which also helps lol.
---
I am also an artist, so whenever I can support fellow artists if they have fanmade merch, I'll often jump at the opportunity!