https://www.amazon.com/dp/B07BHWFH1W/ref=cm_sw_r_cp_apa_fabc_FMYJGXAR31MPCRS0PBXQ

I chose this one because you can change the width. Not the cheapest but not the most expensive. If I remember, I'll let you know how it is after it arrives.

Haha, as /u/Itzslumzy said, it's a bit of a read but think I got most of it.

I built up my gym over time. I was originally in a studio apartment, then upgraded to a one-bedroom to accommodate my workout equipment. Here's what I'm currently rocking with my limited space:

1. Adjustable Olympic Rings. I see you already have them. Instead of a stall bar, I choose to work out outside. Originally because it gave me more space, but also nice not to smell up my place if I can. Plus, and this came later, I do a variety of exercises and sometimes I need more verticality than is offered in my apartment. Especially when I want to get a full lat stretch while hanging, but without bending my knees.
2. I don't have experience with the Domyos Parallels, but I got this instead because I wanted something that connected the two pieces. If you're worried about storage, there are pins along the bar that holds it together to collpase it.
3. I wouldn't discount the cheap interlocking tiles. I currently have these, and they're working out well for me. Personally, I find them less abrasive than some of the rubber mats they have at gyms I've been to. The biggest "downside" to them with a small place is I have 2x as many mats as I need (plus the old ones I replaced them with). Thickness is mostly a matter of preference I found. I needed enough for my knees and for the weights I wanted to leave on them.
4. I like these parallettes, but you have that covered.
5. These bands were bought with muscle-ups in mind. Haven't really utilized them fully yet for that, but they are also good for stretching and targeting smaller muscle groups that don't need as much weight/tension.
6. I'm not sure if they'll ever go back on sale, but I managed to snag these adjustable dumbells for 40% off which is huge savings on something like this. It took forever for me to find something I felt was safe. So far I've been pleased with my purchase.
7. My latest purchase was a result of me wanting to target my upper pecs to round them out better. A lot of the calisthenics exercises I was doing was putting more work into the posterior delts. This bench has been nice so far. I've only had it a few months though, so have yet to find flaws. I haven't needed it yet, but I got a bench that could fold up in the event I need to.

I don't see a problem placing the kallax next to the stall bar. I've seen people exercise in smaller and more confined spaces. You might want to cover the front corner though just in case. Accidents do happen.