I would try to source anything I need a ton of wholesale - I don't have ideas off the top of my head, but I am sure that the wholesale floral district in NYC would be a start in the right direction.
Also this is the prime kind of thing to get a small grant for - you've got a specific need, a specific budget you can come to them with, a great track record (I've seen your work, it's incredible) and you're a grantmaking organization's dream in that regard - it would be a very clean proposal.
I've also got a remission/flare chronic illness - it does make work life interesting.
If I needed to get some fast cash, I honestly would start with supplies and work my way into handmade and more elaborate things. Simply papercrafted tags and cards that people could potentially customize and re-use would sell well, I think. If you can make a simple pattern for something that someone with no experience crafting could buy inexpensively and sell that in volume - that's a good idea too.
I built my main etsy biz on a foundation of sourcing and selling beads, gradually adding some jewelry and eventually transitioning to that.
I'm not trying to be discouraging about selling handmade, this is what worked for me.
I would be certain to know how to use photoshop, CSS, HTML and possibly PHP. Web design is a high ticket item for something that you will save time and headache on if you DIY, and I wish I'd had the opportunity for at least *some* classwork in design, or new media, or internet marketing, or some aspect.
My photoshop and CSS and HTML knowledge is something I use every day and it's an edge I would not want to be without. I'm self taught, and really that's the sweaty hard way to do it. Like I said, I wish I'd taken classes.