Casio SC-800P

I got this for my Roland RD88 on a recommendation, it's a perfect fit.

Zippers seem great and have extra rain shielding. The bag is well padded and there are two large storage pockets on the outside for storing cables or pedals.

It has straps on the back to carry it and a shoulder strap is included, truth be told I feel like those would fail over time but I don't expect to use them much anyway. The shoulder strap hooks are actually metal though.

Recommended for an RD88 at least, and for whatever Casio makes them for. Make sure to check the size if you need one for anything else because it's a really compact bag and fits the small RD88 tightly.