I just started cutting my own bands, so keep in mind I'm a complete newbie. I'll try to include links (I'm in the US so bear that in mind as well) but I might get caught by various filters.

I went with Snipersling for latex. I also got green gatorskin style pouches from them, which I like even if the band holes are really small. I also got crystal string which I haven't used yet.

For tying the bands to the pouches, I use paracord from Amazon and tie a constrictor knot with the inner strand. I highly recommend buying a cheap electric arc lighter to cut/melt the ends. https://www.youtube.com/watch?v=RUylHSoXsuc

I bought this cheap jig. It works so far but I also have forceps as a backup. https://www.amazon.com/Auto-plaza-Slingshot-Catapult-Tying-Making/dp/B08MFB5W4Q

For a rotary cutter, I went with the cheapest Olfa. Fiskars is also a good brand. https://www.amazon.com/OLFA-RTY-2-Splash-Rotary-Cutter/dp/B00C775504

Metric measuring square for measuring and cutting. https://www.amazon.com/Driak-Teacher-0-30cm-0-20cm-Measuring/dp/B07D4GCPBY

I also got a cheap self-healing cutting mat. https://www.amazon.com/Self-Healing-Idemeet-Non-Slip-Double-Sided-Quilting/dp/B091KBZTVD

Any pair of small scissors for trimming the latex ends should work. Finally, I picked up a silver Sharpie to help mark my latex because I'm working with black and yellow.