I think there are a few stores that specializes in just that, legacy V4/M4 figure content support. 

With regards to motive of Content Creator and outlets, while I think most stores got into it for the passion of Art, sustaining the service properly over the long haul requires more than passion it takes dilligence, experience and much resources.  This is because performing customer transactins, and storing and serving large file content in a secure, fast and confident manner costs alot.  A secure ISP and managerd server will cost over $400 a month, not to mention store administration and other labor costs.  The 3D content market is rather niche and small user base, limited to the media formats supported so advertising and other typical monitization efforts to reduce site expenses will not typically begin to cover cost.  So if your passionate to keep content available for your hobby, you may need to charge _something_ for the service to help recover some of the costs. Profitibility is a high goal, break even is still tough because the price point pressure, on older compatable content is huge. Ppeople often expec it should be free or paid for the price of viewing a pop-up ad, but sadly those times burst with the .com crash and the rise of ransomeware thereafter.   THAT is the greatest risk to a content host.  It happens.  So to stay in the game, you need to go pro or go home.  That doesnt need you need to gouge, or put peoples data at risk.  It means you need to charge to make it safe and legit.