I’ve been using Spreadshirt to have a simple branded store (for selling t-shirts, mugs, etc.) that I can easily embed (using an HTML element) on a site built with Bubble. This allows me to keep the store under the same subdomain as the main site, add my own headers and links, etc. to make sure users see the store as a section of my Bubble site. It’s simple to maintain and you don’t have to take care of payments or anything. Just an embed, easy.
However, I’m now tired of Spreadshirt and its low quality products, so I’d like to use some alternative Print On Demand platform. I’ve read about Printify, Printful, Teespring, Gelato… But none of those POD platforms allow embedding a store (you don’t have an out-of-the box store you can embed, instead you have to build a store using its technology). In other words, I don’t see an easy way to integrate them with Bubble. Yeah, I can maybe integrate them via API, but I don’t want to have to take care of payments myself and I want a very simple solution (the store is not our main business, it’s just something we offer to our users to get some fancy merch).
What do you suggest? 
Thanks!